the "quick maths" way is 2000 hours/year 50 weeks, 40 hours per week. Dividing/Multiplying by 2 in your head for quick estimates easy. For more accuracy, do w

the "quick maths" way is 2000 hours/year 50 weeks, 40 hours per week. Dividing/Multiplying by 2 in your head for quick estimates easy. For more accuracy, do what you did.