Not to go all achstuushually on you, but it's even worse.
You can only deduct 10% the first year. Every year after is 20%, then year 6 is a "make up" of the last 10%.
So year 1 would be $90k now not $80k.
> Because of the tax code’s accounting conventions, domestic firms ultimately have to deduct 10 percent of costs in year one, 20 percent of costs each year in years two through five, and the remaining 10 percent of costs in year six.
You can only deduct 10% the first year. Every year after is 20%, then year 6 is a "make up" of the last 10%.
So year 1 would be $90k now not $80k.
> Because of the tax code’s accounting conventions, domestic firms ultimately have to deduct 10 percent of costs in year one, 20 percent of costs each year in years two through five, and the remaining 10 percent of costs in year six.
[0]: https://taxfoundation.org/blog/rd-amortization-impact/