In 1942, the United States implemented a mass payroll tax for employers to help fund World War II. Everything was done manually, since technology didn’t support electronic transfers at the time. It took businesses a lot of time to deduct the taxes from their workers’ paychecks and then mail the money to the IRS. To balance paying their employees and mailing the money to the government, most companies adopted a two-week, semi-monthly, or monthly pay cycle.