to billions of items by the 1950s and tens of billions of items by the mid-1960s. Consequently, it became progressively more difficult for employees who handsorted mail to memorize and keep track of all the individual letter-carrier routes within each city. New technology that allowed mail to be delivered faster also contributed to the pressure for these employees to properly sort the mail. A report tabled in the House of Commons in 1969 dealt with the expected impact of "environmental change" on the Post Office operations over the following 25 years. A key recommendation was the "establishment of a task force to determine the nature of the automation and mechanization the Post Office should adopt, which might include design of a postal code". In December 1969, Communications Minister Eric Kierans announced that a six-character postal code would be introduced, superseding the three-digit zone system. He later tabled a report in February 1970, entitled "A Canadian Public Address Postal Coding System", submitted by the firm of Samson, Belair, Simpson, Riddell Inc. Implementation The introduction of the postal code began with a test in Ottawa on 1 April 1971. Coding of Ottawa was followed by a provincial-level rollout of the system in Manitoba, and the system was gradually implemented in the rest of the country from 1972 to 1974, although the nationwide use of the code by the end of 1974 was only 38.2 per cent. The introduction of such a code system allowed Canada Post to easily speed up and simplify the flow of mail in the country, with sorting machines being able to handle 26,640 objects an hour. The Canadian Union of Postal Workers objected to the automated sorting system mainly because the wages of those who ran the new automated machines were much lower than those who had hand-sorted mail. The unions ended up staging job action and public information campaigns, with the message that they did not want people and business to use postal codes on their mail. The union declared 20 March 1975 National "Boycott the Postal Code" Day, also demanding a reduction in the work week from 40 to 30 hours. The boycott was called off in February 1976. One 1975 advertisement in the Toronto magazine Byliner generated controversy by showing a man writing a postal code on the bottom of a thonged woman with the following ditty: "We're not 'stringing' you along, Use postal codes