you need more knowledge of math too it sounds like. the shockingly simple math factors out inflation it doesn't matter what median is today vs 20 years from now you figure everything in today dollars and factor out inflation. 53k would buy 29k worth of stuff in 1984 based on inflation so discretionary spending has increased if you really want to point a finger at something. someone in 1984 could be spending/saving almost 33% of their salary with the CPI adjusted median of 2004.

EDIT, sorry Slow2FIRE, I did my calcs before I saw your post.

OK, I slogged through an OpenOffice calculation.

I used a starting date of 1987 with $25k of earnings and a 30% of gross savings rate.

I incremented income by the yearly inflation rate using this calculator.

http://www.westegg.com/inflation/I used 1987 to 2016, ending income was $55,474.

I checked each year and increased the income by that years inflation rate.

For each year, I used A=P(1+r/n)^(nt)

to calculate the growth at 5%.

Where;

A = Future Value

P = amount invested each year

r = Interest Rate

n = The number of times that interest is compounded per year.

t = The number of years money is invested.

I then added all the investments and growth for each year with a result of,

$791,2555 at 4% SWR this is $31,650.

At the end 2016 my $25k inflation adjusted was up to $55,474.

$55,474 - 30% = $38,832.

So the 4% SWR will not earn you $38,832 that you have been living on, But,

1- Your income will probably grow faster than inflation as you gain experience.

2- I think the 5% growth is a little low, for a market return.

4 - I was more than fair adding interest 12 times a year.

4 - This also assumes Zero taxes on savings.

I may do this again using median income which is slightly lower that

the incomes used above.

Looks to me, that if you are a median income earner, and you do everything right,

ER is will not be very early, BUT you will live very well with your stash and SS.

If anyone wants to massage my numbers or check them,

I could send the Open Office file to you, (you might need to tell me how).

Might be easier to start from scratch, it only took about an hour and 15 minutes,

and that was with me searching google to learn how to do certain functions in Open Office.