Question: Use the census wage data for 1990 for this question. The last column in this spreadsheet is wage and salary income for the year, which can equal to zero (e.g. for the self-employed). For this question, use only those individuals with nonzero wage and salary income. Create a weekly “wage” by dividing total wage and salary income by weeks worked and call it W.

Run an OLS regression of W on a constant, a male/female indicator, age, and age squared to estimate quadratic age-profiles for men and women that are the same shape except for a vertical shift. Plot the profiles implied by your point estimates over the range of 18 to 65 years of age on the same graph. What is a point estimate for the age at which the profiles peak?