I'm not going to tell you to do either. Rather, I'm going to advise that you crunch some numbers.

You're 47 and plan on working until at least 63. That's 16 years to keep 80% of your pay.

If we assume a salary of $100k and 3% raises each year, you end up earning about 1.5x your current salary in 15 years.

100% 80%

Year 1 $100,000.00 $80,000.00

Year 2 $103,000.00 $82,400.00

Year 3 $106,090.00 $84,872.00

Year 4 $109,272.70 $87,418.16

Year 5 $112,550.88 $90,040.70 13% increase from original salary

Year 6 $115,927.41 $92,741.93

Year 7 $119,405.23 $95,524.18

Year 8 $122,987.39 $98,389.91

Year 9 $126,677.01 $101,341.61

Year 10 $130,477.32 $104,381.85 30% increase from original salary

Year 11 $134,391.64 $107,513.31

Year 12 $138,423.39 $110,738.71

Year 13 $142,576.09 $114,060.87

Year 14 $146,853.37 $117,482.70

Year 15 $151,258.97 $121,007.18 51% increase from original salary

Year 16 $155,796.74 $124,637.39

We need to throw away years 1-6 because no matter what you do, you're paying that 20% as long as you live in France with no French degree.

I don't know what tax percentage you'd pay with a local degree so I'm assuming 0% which is obviously wrong but you'll need to plug your numbers in to make this applicable to you anyhow so you can recalculate correctly if you'd like.

If you don't get the degree, your total earnings from year 7 on would be $1,095,077.

If you get the degree, your total earnings from year 7 on would be $1,368,847.

**Difference being $273,769 - 6 years of school at $400 totals to $271,369**

Let's take it one step further.

If you took that extra 20% at the end of the year and invested all of it and let compounding interest do it's thing (compounded 4 times annually with a 7% return), you'd end up with:

20% Year End Investment Balance

Year 7 $23,881.05 $23,881.05

Year 8 $24,597.48 $53,801.53

Year 9 $25,335.40 $84,823.63

Year 10 $26,095.46 $118,889.63

Year 11 $26,878.33 $156,242.71

Year 12 $27,684.68 $197,144.23

Year 13 $28,515.22 $241,875.11

Year 14 $29,370.67 $290,737.25

Year 15 $30,251.79 $344,055.00

Year 16 $31,159.35 $402,176.89

*Think I messed up the math on the first two years of the compounding (start dates confused me) but I'm sure you catch my drift.

My math might not be perfect (anyone is welcome to double check) but I hope you can see what your trade off's are now.