what is your time worth?

So i used to have a hard time deciding what projects to take on and what to avoid. Here is what i came up with.

yearly net earnings / hours worked = hourly rate

example $100,000 / 2000 = $50



From that i was able to determine my baseline as 40%, so i will not even take on a project lower than $20 hr, based on the example provided. Projects in the 40%-60% percent range i still try to work into my schedule in my idle time. Projects higher than 60% i work on during my primetime hours (the first 10 hours of the day). I am now able to maximize efficiency and production.