gistfile1.rb

tax_modifier = 0.015

tax = 0.6
after_tax = 400000.0

while tax >= 0 do

  if after_tax > 35000.0
    income = after_tax / (1.0 - tax)
  else
    tax = 0.0
    income = after_tax
  end

  puts sprintf("%3s  %-8s  %-8s", "%.0f%%" % (100 * tax), "$%.0f" % income, "$%.0f" % after_tax)

  tax -= tax_modifier
  after_tax -= 10000.0
end

60%  $1000000  $400000 
58%  $939759   $390000 
57%  $883721   $380000 
55%  $831461   $370000 
54%  $782609   $360000 
52%  $736842   $350000 
51%  $693878   $340000 
49%  $653465   $330000 
48%  $615385   $320000 
46%  $579439   $310000 
45%  $545455   $300000 
43%  $513274   $290000 
42%  $482759   $280000 
40%  $453782   $270000 
39%  $426230   $260000 
37%  $400000   $250000 
36%  $375000   $240000 
34%  $351145   $230000 
33%  $328358   $220000 
31%  $306569   $210000 
30%  $285714   $200000 
28%  $265734   $190000 
27%  $246575   $180000 
25%  $228188   $170000 
24%  $210526   $160000 
22%  $193548   $150000 
21%  $177215   $140000 
19%  $161491   $130000 
18%  $146341   $120000 
16%  $131737   $110000 
15%  $117647   $100000 
13%  $104046   $90000  
12%  $90909    $80000  
10%  $78212    $70000  
 9%  $65934    $60000  
 7%  $54054    $50000  
 6%  $42553    $40000  
 0%  $30000    $30000