Actually, my guess is the every-four-weeks bit is to goose revenue. With monthly, you're getting paid 12 times a year. With every four weeks, you get paid 13 t

Actually, my guess is the every-four-weeks bit is to goose revenue. With monthly, you're getting paid 12 times a year. With every four weeks, you get paid 13 times. It's a nifty little sales trick. Most people (including me) automatically round four weeks up to a month before thinking about it.