Gyroscopic Investing

Hal wrote: ↑Mon Apr 06, 2020 2:27 am

Smith1776 wrote: ↑Mon Apr 06, 2020 12:35 am Libertarian666's portfolio, with its zero stock allocation, reminds me of the old martial arts master that beats the big villain with just his fists -- no weapons at all.

Hiyah!!!

Is this how you picture Libertarian666 ?

Where did you get that picture? Now my cover is blown!

Exactly!! Or, another character comes to mind. Nicholai, from Resident Evil 3. He runs around with nothing but a pistol with ONE CLIP and a friggin' knife but somehow always manages to get the highest scores in mercenary mode.

I like the Libertarian666 portfolio because it's so... novel.

This is piquing my interest. Here's a 10,000 ft view of the Tech Portfolio.

Oh man, my hands are itching to 'optimize' that chart by adding some stocks and/or bonds
Not doing it!

WhiteElephant wrote: ↑Mon Apr 06, 2020 10:45 am Oh man, my hands are itching to 'optimize' that chart by adding some stocks and/or bonds
Not doing it!

And some long bonds.

But yeah, I'm surprised that the backtest looks as good as it does. Those short treasury bonds really picked up the slack in the 1981 to 2000 bear market for gold.

That chart seems like it is basically an inverse of the value of a dollar.

fireplan wrote: ↑Sun Mar 29, 2020 6:40 am

Libertarian666 wrote: ↑Sat Mar 28, 2020 8:45 am 2/3rd actual physical gold (geographically diverse)
1/3rd US T-Bills

Comments?

No doubt there are periods when this portfolio will do quite well, and the next 10-20 years could very well be one of them, but...

If you plug this into portfoliocharts.com, this portfolio is impressive in the fact that it comes out dead last or second to last in every metric! Gold makes a great diversifier to balance the gyroscope, but gold can also have decades of negative performance, so a portfolio with 2/3rds gold and no equities or LTTs is highly unbalanced and thus very risky on a long term basis.

For me, as an early retiree, I find the perpetual withdrawal rate (PWR) of a portfolio to be the best measure of the risk vs reward of that portfolio, as it encapsulates the long term CAGR, volatility, length and depth of drawdowns, all into a single metric that directly corresponds to expected lifetime income from the investment.

A portfolio of 2/3rds gold and 1/3rd US T-Bills has a historical PWR (out to 40 years) of only 0.3%, meaning you would need a $10 million portfolio just to harvest $30k a year from it. In comparison, a total stock market portfolio, which sounds very risky in comparison, has a 3.6% PWR at 40 years, which makes it 12x less risky by this metric.

i agree .... far to risky and certainly in our case would never have given us the growth we needed to retire .

i believe in planning around what was , what is , and what stands a reasonable chance of continuing ....


a penny saved is a penny earned but without good compounding it will always stay a penny or less...

i also would never go back to the 1970's ... owning stocks and commodities or gold was not something the public did as a whole ...there were no 401ks and most of us or our parents had most of their money in banks . throw in the high frequency trading that dominates 90% of each days volume and you are fighting yesterdays war .

so i would certainly want far more diversification then a bad news portfolio.

i mean if you wait for a bear markets in equities to start comparing to other assets , that to is not going to be accurate either ....

we spend 80% of our time somewhere between the last low and last high ..... so say comparing a decade or two of gold to a bear market in stocks would not be a good comparison

One perspective is that if you are a high earner / saver this may be a high probability plan. Fireplan mentioned a .3 percent perpetual withdrawal rate of 10 million. But the actual withdrawal rate is pretty high. 250k for 40 years not counting any other forms of income such as social security.

Personally I didn’t work a lifetime and scrimp ,Save and invest just so I can draw peanuts out of it in the last down of our lives ...quite frankly any draw less than 3.50% or so would be inefficient use of money I could be enjoying . As it is a 4% swr left you with more than you started 90% of the 120 30 year cycles we had to date.

We are retired but if we could double our assets I would simply enjoy spending that much more

mathjak107 wrote: ↑Tue May 05, 2020 1:46 pm Personally I didn’t work a lifetime and scrimp ,Save and invest just so I can draw peanuts out of it in the last down of our lives ...quite frankly any draw less than 3.50% or so would be inefficient use of money I could be enjoying . As it is a 4% swr left you with more than you started 90% of the 120 30 year cycles we had to date.

We are retired but if we could double our assets I would simply enjoy spending that much more

If you could increase your assets 100% by what corresponding percentage would you increase your spending?

For me I'd say zero % because I got to the amount of assets I have by being extremely frugal. It's my DNA. To buy a lot of things I never have (while easily affording to) goes against all my ways.

Vinny

yankees60 wrote: ↑Tue May 05, 2020 7:47 pm

mathjak107 wrote: ↑Tue May 05, 2020 1:46 pm Personally I didn’t work a lifetime and scrimp ,Save and invest just so I can draw peanuts out of it in the last down of our lives ...quite frankly any draw less than 3.50% or so would be inefficient use of money I could be enjoying . As it is a 4% swr left you with more than you started 90% of the 120 30 year cycles we had to date.

We are retired but if we could double our assets I would simply enjoy spending that much more

If you could increase your assets 100% by what corresponding percentage would you increase your spending?

For me I'd say zero % because I got to the amount of assets I have by being extremely frugal. It's my DNA. To buy a lot of things I never have (while easily affording to) goes against all my ways.

Vinny

i sure would increase spending likely proportionately ... our want to do list is longer than our funds are ... if we couldnt find things to spend it on for ourselves , well we have 6 grand kids .

i have no desire to die with the biggest pile nor did i work , save and do without many times trying to get the retirement pile as big as we could , just to look at it

mathjak107 wrote: ↑Wed May 06, 2020 4:04 am

yankees60 wrote: ↑Tue May 05, 2020 7:47 pm

mathjak107 wrote: ↑Tue May 05, 2020 1:46 pm Personally I didn’t work a lifetime and scrimp ,Save and invest just so I can draw peanuts out of it in the last down of our lives ...quite frankly any draw less than 3.50% or so would be inefficient use of money I could be enjoying . As it is a 4% swr left you with more than you started 90% of the 120 30 year cycles we had to date.

We are retired but if we could double our assets I would simply enjoy spending that much more

If you could increase your assets 100% by what corresponding percentage would you increase your spending?

For me I'd say zero % because I got to the amount of assets I have by being extremely frugal. It's my DNA. To buy a lot of things I never have (while easily affording to) goes against all my ways.

Vinny

i sure would increase spending likely proportionately ... our want to do list is longer than our funds are ... if we couldnt find things to spend it on for ourselves , well we have 6 grand kids .

i have no desire to die with the biggest pile nor did i work , save and do without many times trying to get the retirement pile as big as we could , just to look at it

I am the ultimate security seeking personality so there is never too much. Plus, how would deal with this one?

There could arise some medical breakthrough that could truly extend your life in a meaningful way. The catch is that no private insurance or Medicare would pay a cent towards it. It would be equivalent in cost to 1/2 or more of your present portfolio. Would you ever want to set a aside a large part of your portfolio for the low probability that could be a possibly for you later in life?

Vinny

Vinny

just maintaining a 4% inflation adjusted draw off the balance for 30 years generally leaves a lot not spent regardless of amount .

we had 120 actual 30 year retirement cycles to date ...

with 50/50 to 60/40

90% of the time it left you with more than you started , 67% of the time you were left with 2x what you started , 50% of the time it left you with 3x what you started ...in fact the odds of failure are the same odds as ending with 6x what you started with .

so even sticking to 4% of your balance has in my opinion way to much most likely left for even the odds of living longer.

certainly raises would be in order along the way .

mathjak107 wrote: ↑Wed May 06, 2020 9:01 am just maintaining a 4% inflation adjusted draw off the balance for 30 years generally leaves a lot not spent regardless of amount .

we had 120 actual 30 year retirement cycles to date ...

with 50/50 to 60/40

90% of the time it left you with more than you started , 67% of the time you were left with 2x what you started , 50% of the time it left you with 3x what you started ...in fact the odds of failure are the same odds as ending with 6x what you started with .

so even sticking to 4% of your balance has in my opinion way to much most likely left for even the odds of living longer.

certainly raises would be in order along the way .

It's possible for me in my frugal lifestyle to actually live off the social security which I will finally have to start collecting next year. Therefore, a large portion of my portfolio could be viewed as a huge self-insured medical insurance policy for some great procedure that would have to be self-paid.

Vinny

mathjak107 wrote: ↑Wed May 06, 2020 9:01 am just maintaining a 4% inflation adjusted draw off the balance for 30 years generally leaves a lot not spent regardless of amount .

we had 120 actual 30 year retirement cycles to date ...

with 50/50 to 60/40

90% of the time it left you with more than you started , 67% of the time you were left with 2x what you started , 50% of the time it left you with 3x what you started ...in fact the odds of failure are the same odds as ending with 6x what you started with .

so even sticking to 4% of your balance has in my opinion way to much most likely left for even the odds of living longer.

certainly raises would be in order along the way .

Wow, I didn't know that we had 360 years of retirement data!

Libertarian666 wrote: ↑Wed May 06, 2020 10:25 am

mathjak107 wrote: ↑Wed May 06, 2020 9:01 am just maintaining a 4% inflation adjusted draw off the balance for 30 years generally leaves a lot not spent regardless of amount .

we had 120 actual 30 year retirement cycles to date ...

with 50/50 to 60/40

90% of the time it left you with more than you started , 67% of the time you were left with 2x what you started , 50% of the time it left you with 3x what you started ...in fact the odds of failure are the same odds as ending with 6x what you started with .

so even sticking to 4% of your balance has in my opinion way to much most likely left for even the odds of living longer.

certainly raises would be in order along the way .

Wow, I didn't know that we had 360 years of retirement data!

It's not 360 years. It is 120 rolling years....1990 to 2019 would be one, 1989 to 2018 would be another and so on.

Vinny

yankees60 wrote: ↑Wed May 06, 2020 10:47 am

Libertarian666 wrote: ↑Wed May 06, 2020 10:25 am

mathjak107 wrote: ↑Wed May 06, 2020 9:01 am just maintaining a 4% inflation adjusted draw off the balance for 30 years generally leaves a lot not spent regardless of amount .

we had 120 actual 30 year retirement cycles to date ...

with 50/50 to 60/40

90% of the time it left you with more than you started , 67% of the time you were left with 2x what you started , 50% of the time it left you with 3x what you started ...in fact the odds of failure are the same odds as ending with 6x what you started with .

so even sticking to 4% of your balance has in my opinion way to much most likely left for even the odds of living longer.

certainly raises would be in order along the way .

Wow, I didn't know that we had 360 years of retirement data!

It's not 360 years. It is 120 rolling years....1990 to 2019 would be one, 1989 to 2018 would be another and so on.

Vinny

In other words, you are reusing the same data, not independent data.
This greatly reduces the value of the analysis.

Libertarian666 wrote: ↑Wed May 06, 2020 10:53 am

yankees60 wrote: ↑Wed May 06, 2020 10:47 am

Libertarian666 wrote: ↑Wed May 06, 2020 10:25 am

mathjak107 wrote: ↑Wed May 06, 2020 9:01 am just maintaining a 4% inflation adjusted draw off the balance for 30 years generally leaves a lot not spent regardless of amount .

we had 120 actual 30 year retirement cycles to date ...

with 50/50 to 60/40

90% of the time it left you with more than you started , 67% of the time you were left with 2x what you started , 50% of the time it left you with 3x what you started ...in fact the odds of failure are the same odds as ending with 6x what you started with .

so even sticking to 4% of your balance has in my opinion way to much most likely left for even the odds of living longer.

certainly raises would be in order along the way .

Wow, I didn't know that we had 360 years of retirement data!

It's not 360 years. It is 120 rolling years....1990 to 2019 would be one, 1989 to 2018 would be another and so on.

Vinny

In other words, you are reusing the same data, not independent data.
This greatly reduces the value of the analysis.

Not me. Mathjak. And, yes, that is a common criticism of using rolling data in this way.

Vinny

Libertarian666 wrote: ↑Wed May 06, 2020 10:53 am

yankees60 wrote: ↑Wed May 06, 2020 10:47 am

Libertarian666 wrote: ↑Wed May 06, 2020 10:25 am

mathjak107 wrote: ↑Wed May 06, 2020 9:01 am just maintaining a 4% inflation adjusted draw off the balance for 30 years generally leaves a lot not spent regardless of amount .

we had 120 actual 30 year retirement cycles to date ...

with 50/50 to 60/40

90% of the time it left you with more than you started , 67% of the time you were left with 2x what you started , 50% of the time it left you with 3x what you started ...in fact the odds of failure are the same odds as ending with 6x what you started with .

so even sticking to 4% of your balance has in my opinion way to much most likely left for even the odds of living longer.

certainly raises would be in order along the way .

Wow, I didn't know that we had 360 years of retirement data!

It's not 360 years. It is 120 rolling years....1990 to 2019 would be one, 1989 to 2018 would be another and so on.

Vinny

In other words, you are reusing the same data, not independent data.
This greatly reduces the value of the analysis.

It does not reduce the value of the analysis at all. It is important to look at every possible start and end year. You average them together to get a more accurate picture. This is exactly how Tyler does the analysis on his website. It's an angle that most people fail to look at, and it holds a lot of value to take rolling periods into account on top of just absolute returns from some arbitrary start and end date.

pmward wrote: ↑Wed May 06, 2020 11:38 am

Libertarian666 wrote: ↑Wed May 06, 2020 10:53 am

yankees60 wrote: ↑Wed May 06, 2020 10:47 am

Libertarian666 wrote: ↑Wed May 06, 2020 10:25 am

mathjak107 wrote: ↑Wed May 06, 2020 9:01 am just maintaining a 4% inflation adjusted draw off the balance for 30 years generally leaves a lot not spent regardless of amount .

we had 120 actual 30 year retirement cycles to date ...

with 50/50 to 60/40

90% of the time it left you with more than you started , 67% of the time you were left with 2x what you started , 50% of the time it left you with 3x what you started ...in fact the odds of failure are the same odds as ending with 6x what you started with .

so even sticking to 4% of your balance has in my opinion way to much most likely left for even the odds of living longer.

certainly raises would be in order along the way .

Wow, I didn't know that we had 360 years of retirement data!

It's not 360 years. It is 120 rolling years....1990 to 2019 would be one, 1989 to 2018 would be another and so on.

Vinny

In other words, you are reusing the same data, not independent data.
This greatly reduces the value of the analysis.

It does not reduce the value of the analysis at all. It is important to look at every possible start and end year. You average them together to get a more accurate picture. This is exactly how Tyler does the analysis on his website. It's an angle that most people fail to look at, and it holds a lot of value to take rolling periods into account on top of just absolute returns from some arbitrary start and end date.

You don't agree that a set of totally independent data points are going to be more valid than an equal number of data points that have significant overlaps between those data points?

Vinny

yankees60 wrote: ↑Wed May 06, 2020 11:43 am

pmward wrote: ↑Wed May 06, 2020 11:38 am

Libertarian666 wrote: ↑Wed May 06, 2020 10:53 am

yankees60 wrote: ↑Wed May 06, 2020 10:47 am

Libertarian666 wrote: ↑Wed May 06, 2020 10:25 am

mathjak107 wrote: ↑Wed May 06, 2020 9:01 am just maintaining a 4% inflation adjusted draw off the balance for 30 years generally leaves a lot not spent regardless of amount .

we had 120 actual 30 year retirement cycles to date ...

with 50/50 to 60/40

90% of the time it left you with more than you started , 67% of the time you were left with 2x what you started , 50% of the time it left you with 3x what you started ...in fact the odds of failure are the same odds as ending with 6x what you started with .

so even sticking to 4% of your balance has in my opinion way to much most likely left for even the odds of living longer.

certainly raises would be in order along the way .

Wow, I didn't know that we had 360 years of retirement data!

It's not 360 years. It is 120 rolling years....1990 to 2019 would be one, 1989 to 2018 would be another and so on.

Vinny

In other words, you are reusing the same data, not independent data.
This greatly reduces the value of the analysis.

It does not reduce the value of the analysis at all. It is important to look at every possible start and end year. You average them together to get a more accurate picture. This is exactly how Tyler does the analysis on his website. It's an angle that most people fail to look at, and it holds a lot of value to take rolling periods into account on top of just absolute returns from some arbitrary start and end date.

You don't agree that a set of totally independent data points are going to be more valid than an equal number of data points that have significant overlaps between those data points?

Vinny

I think they both have value. One gives you a nice average of time periods, like Tyler uses. The other gives you independent time frames to analyze. There is nothing wrong with either, and it's good to look at both, imo. Both have their biases. Both have their strengths and weaknesses. Both ways are simply clues, small puzzle pieces that form the whole picture.

yankees60 wrote: ↑Wed May 06, 2020 10:47 am

Libertarian666 wrote: ↑Wed May 06, 2020 10:25 am

mathjak107 wrote: ↑Wed May 06, 2020 9:01 am just maintaining a 4% inflation adjusted draw off the balance for 30 years generally leaves a lot not spent regardless of amount .

we had 120 actual 30 year retirement cycles to date ...

with 50/50 to 60/40

90% of the time it left you with more than you started , 67% of the time you were left with 2x what you started , 50% of the time it left you with 3x what you started ...in fact the odds of failure are the same odds as ending with 6x what you started with .

so even sticking to 4% of your balance has in my opinion way to much most likely left for even the odds of living longer.

certainly raises would be in order along the way .

Wow, I didn't know that we had 360 years of retirement data!

It's not 360 years. It is 120 rolling years....1990 to 2019 would be one, 1989 to 2018 would be another and so on.

Vinny

yes it is 120 - rolling 30 year cycles

pmward wrote: ↑Wed May 06, 2020 11:45 am

yankees60 wrote: ↑Wed May 06, 2020 11:43 am

pmward wrote: ↑Wed May 06, 2020 11:38 am

Libertarian666 wrote: ↑Wed May 06, 2020 10:53 am

yankees60 wrote: ↑Wed May 06, 2020 10:47 am

Libertarian666 wrote: ↑Wed May 06, 2020 10:25 am

mathjak107 wrote: ↑Wed May 06, 2020 9:01 am just maintaining a 4% inflation adjusted draw off the balance for 30 years generally leaves a lot not spent regardless of amount .

we had 120 actual 30 year retirement cycles to date ...

with 50/50 to 60/40

90% of the time it left you with more than you started , 67% of the time you were left with 2x what you started , 50% of the time it left you with 3x what you started ...in fact the odds of failure are the same odds as ending with 6x what you started with .

so even sticking to 4% of your balance has in my opinion way to much most likely left for even the odds of living longer.

certainly raises would be in order along the way .

Wow, I didn't know that we had 360 years of retirement data!

It's not 360 years. It is 120 rolling years....1990 to 2019 would be one, 1989 to 2018 would be another and so on.

Vinny

In other words, you are reusing the same data, not independent data.
This greatly reduces the value of the analysis.

It does not reduce the value of the analysis at all. It is important to look at every possible start and end year. You average them together to get a more accurate picture. This is exactly how Tyler does the analysis on his website. It's an angle that most people fail to look at, and it holds a lot of value to take rolling periods into account on top of just absolute returns from some arbitrary start and end date.

You don't agree that a set of totally independent data points are going to be more valid than an equal number of data points that have significant overlaps between those data points?

Vinny

I think they both have value. One gives you a nice average of time periods, like Tyler uses. The other gives you independent time frames to analyze. There is nothing wrong with either, and it's good to look at both, imo. Both have their biases. Both have their strengths and weaknesses. Both ways are simply clues, small puzzle pieces that form the whole picture.

all we are really interested in is the worst time frames retirees have hit ... 1907,1929,1937 , 1965 ,1966 were the worst on record and the poster children for the worst outcomes and the time frames safe withdrawal rates were based on .....

michael kitces did some heavy duty numbers crunching and found all the worst time frames had one common denominator ...everyone failed to hold 4% when the real return average fell below 2% over the the first 15 years .

so all the other time frames are really not needed now that we understand the math behind the failures .

just monitor it along the way .... if 5 years years in you are less than 2% real return a red flag should go up

yankees60 wrote: ↑Wed May 06, 2020 11:43 am

pmward wrote: ↑Wed May 06, 2020 11:38 am

Libertarian666 wrote: ↑Wed May 06, 2020 10:53 am

yankees60 wrote: ↑Wed May 06, 2020 10:47 am

Libertarian666 wrote: ↑Wed May 06, 2020 10:25 am

mathjak107 wrote: ↑Wed May 06, 2020 9:01 am just maintaining a 4% inflation adjusted draw off the balance for 30 years generally leaves a lot not spent regardless of amount .

we had 120 actual 30 year retirement cycles to date ...

with 50/50 to 60/40

90% of the time it left you with more than you started , 67% of the time you were left with 2x what you started , 50% of the time it left you with 3x what you started ...in fact the odds of failure are the same odds as ending with 6x what you started with .

so even sticking to 4% of your balance has in my opinion way to much most likely left for even the odds of living longer.

certainly raises would be in order along the way .

Wow, I didn't know that we had 360 years of retirement data!

It's not 360 years. It is 120 rolling years....1990 to 2019 would be one, 1989 to 2018 would be another and so on.

Vinny

In other words, you are reusing the same data, not independent data.
This greatly reduces the value of the analysis.

It does not reduce the value of the analysis at all. It is important to look at every possible start and end year. You average them together to get a more accurate picture. This is exactly how Tyler does the analysis on his website. It's an angle that most people fail to look at, and it holds a lot of value to take rolling periods into account on top of just absolute returns from some arbitrary start and end date.

You don't agree that a set of totally independent data points are going to be more valid than an equal number of data points that have significant overlaps between those data points?

Vinny

no , because thanks to kitces doing the numbers crunching all we need to know is the math behind the failures ..they all failed for the same reason mathematically

suppose you were so unlucky to retire in one of those worst time frames ,what would your 30 year results look like :

1907 stocks returned 7.77% -- bonds 4.250-- rebalanced portfolio 7.02- - inflation 1.64--

1929 stocks 8.19% - - bonds 1.74%-- rebalanced portfolio 6.28-- inflation 1.69--

1937 stocks 10.12 - - bonds 2.13 - rebalanced portfolio -- 7.24 inflation-- 2.82

1966 stocks 10.23 - -bonds 7.85 -- rebalanced portfolio 9.56- - inflation 5.38

for comparison the 140 year average's were:

stocks 8.39--bonds 2.85%--rebalanced portfolio 6.17% inflation 2.23%

so what made those time frames the worst ? what made them the worst is the fact in every single retirement time frame the outcome of that 30 year period was determined not by what happened over the 30 years but the entire outcome was decided in the first 15 years.

so lets look at the first 15 years in those time frames determined to be the worst we ever had.

1907--- stocks minus 1.47%---- bonds minus .39%-- rebalanced minus .70% ---inflation 1.64%

1929---stocks 1.07%---bonds 1.79%---rebalanced 2.29%--inflation 1.69%

1937---stocks -- 3.45%---bonds minus 3.07%-- rebalanced 1.23%--inflation 2.82%

1966-stocks minus .13%--bonds 1.08%--rebalanced .64%-- inflation 5.38%

it is those 15 year horrible time frames that the 4% safe withdrawal rate was born out of since you had to reduce from what could have been 6.50% as a swr down to just 4% to get through those worst of times.

while 6.50% to 4% does not sound like a lot 1 million at 4% is an initial draw rate of 40k , at 6.50% you could have had 65k . that is a whopping 60% more .

so what it boils down to is any time you fall below a 2% real return average over the first 15 years you run the danger of 4% not holding. but even a 1/2% cut in spending will make you whole again over the next 15 years or longer.

pmward wrote: ↑Wed May 06, 2020 11:38 am

Libertarian666 wrote: ↑Wed May 06, 2020 10:53 am

yankees60 wrote: ↑Wed May 06, 2020 10:47 am

Libertarian666 wrote: ↑Wed May 06, 2020 10:25 am

mathjak107 wrote: ↑Wed May 06, 2020 9:01 am just maintaining a 4% inflation adjusted draw off the balance for 30 years generally leaves a lot not spent regardless of amount .

we had 120 actual 30 year retirement cycles to date ...

with 50/50 to 60/40

90% of the time it left you with more than you started , 67% of the time you were left with 2x what you started , 50% of the time it left you with 3x what you started ...in fact the odds of failure are the same odds as ending with 6x what you started with .

so even sticking to 4% of your balance has in my opinion way to much most likely left for even the odds of living longer.

certainly raises would be in order along the way .

Wow, I didn't know that we had 360 years of retirement data!

It's not 360 years. It is 120 rolling years....1990 to 2019 would be one, 1989 to 2018 would be another and so on.

Vinny

In other words, you are reusing the same data, not independent data.
This greatly reduces the value of the analysis.

It does not reduce the value of the analysis at all. It is important to look at every possible start and end year. You average them together to get a more accurate picture. This is exactly how Tyler does the analysis on his website. It's an angle that most people fail to look at, and it holds a lot of value to take rolling periods into account on top of just absolute returns from some arbitrary start and end date.

to take it a step further , not only does what happens before and after the time frame you are looking at matter but so does how much you have invested at the time matter .

what happens now to my portfolio in dollars up or down is far greater of an impact then the same moves 30 years ago .

so it is all well and good i was part of th 1980's bull market , but the time frame leading in was some of the worst in history with markets dead for 20 years ... we had little money yet to take part in the great bull ... the size of your portfolio and when , can matter more than the market return itself .

so leading in and next up time frames matter a lot .