This analysis of social media usage is based on a compilation of 27 surveys and about 47,000 interviews among adult internet users and about 62,000 interviews among all adults conducted by Pew Research Center from March 2005 to July 2015. These surveys are combined, allowing for comparisons of trends among different demographic groups across years. Yearly totals are calculated by combining all surveys for the calendar year with appropriate weights applied. Weighting to adjust for disproportionate sampling and nonresponse reduces the precision of estimates beyond what would be achieved under simple random sampling. In this report, all measures of sampling error and statistical tests of significance take into account the design effect of weighting. The tables below show the number of surveys and interviews conducted each year for internet users and all adults respectively, as well as the margin of error for each yearly sample.
