I am working with the BCS1970 Data Set and currently looking at the net pay variable. Each individual had to give their net pay and then what time period this covered. 5 periods were given as options : one week, a fortnight, four weeks, a calendar month and a year. As 63% gave their net pay in one calendar month, I want to convert the remaining 37% of answers to that time period ( ie multiply the ones who answered in weekly pay by 4 ...).

How would I go about this please?

Thank you very much.