Demurrage-charged local currency was successfully tested in the Austrian town of Wörgl between 1932 and 1934, as a tax collected for the benefit of the unemployed, until the Austrian central bank stopped the experiment. Similarly, in 1936, the Social Credit Party-led government in Alberta, Canada, introduced prosperity certificates in an attempt to alleviate the effects of the Great Depression, with holders having to affix to the back of a certificate a 1-cent stamp before the end of every week, for the certificate to maintain its validity. Local scrip systems, many of which incorporated demurrage fees, were also used across the United States during the Great Depression, and the Bankhead–Pettengill bill of 17 February 1933 was introduced in Congress to institutionalize such a system at the national level under the US Treasury, as documented in Irving Fisher's book "Stamp Scrip."