steven nelms writes that he ` ca n't afford ' his wife to be stay-at-home mom .
he calculates the monetary value of what she contributes to the home , including child care , cooking , cleaning and running the finances .
nelms concludes that his wife 's annual salary should be $ 73,960 .
he writes that he was ` ashamed ' that his wife ever ` felt like she does n't have just as much right to our income as i do '
nelms said his wife has worked since she was 14 and he wanted to make sure she felt appreciated .