Was this comment really worth exposing the fact that you don't understand why nearly every store in America prices with 9's?
But since you asked... lowering the price by $11 will require 28% more unit sales to cover the difference. Normally 28% more units would increase COGS, resulting in less profit on equivalent sales, requiring even larger unit growth, but we're talking about software here so let's ignore that. Regardless, I couldn't tell you which works better without some more data.
I will bet you, however, that $39 will outperform $40 in total revenue and profit.
But since you asked... lowering the price by $11 will require 28% more unit sales to cover the difference. Normally 28% more units would increase COGS, resulting in less profit on equivalent sales, requiring even larger unit growth, but we're talking about software here so let's ignore that. Regardless, I couldn't tell you which works better without some more data.
I will bet you, however, that $39 will outperform $40 in total revenue and profit.