The Socialist Party giving its monthly membership figures to defend the perception of losing numbers, down from the Election Year of 1912’s average of 118,000 members per month.
The Party Builder. Official National Bulletin of the Socialist Party. No. 58. December 13, 1913.
For a variety of reasons, the national Socialist Party of America did not have an official publication until May 1904 when the national convention mandated the monthly Socialist Party Official Bulletin as a way for the Party to communicate to its members. The name was changed to Socialist Party Monthly Bulletin in October 1911. The Party Builder became the name in 1913 and also became a subscription paper and a weekly. In 1914 the Socialist Party replaced The Party Builder with a regular propaganda newspaper, The American Socialist. These Party paper contain National Committee and National Executive Committee minutes, National Secretary reports, membership figures, financial statements, letters from party members, articles by prominent party leaders, and the figures for election of party officers and internal questions.
PDF of issue: https://www.marxists.org/history/usa/pubs/spa-bulletins/131213-partybuilder-w58.pdf