Level from College Savings Plan Network (CSPN) and Strategic Insight (SI). From 1996:Q4 to 1999:Q4, only annual level data are available. Unpublished semiannual data are used from 2000:Q2 to 2016:Q4, except for 2009:Q2. Levels from 2017:Q1 to 2017:Q4 are estimated based on previous CSPN data and current SI topline data. Quarterly data are linearly interpolated from annual and semiannual levels. Transactions are calculated as the change in level. For quarters after the most recent CSPN data, unadjusted transactions are estimated using a 12 quarter average.
Last edited on: 03/23/2018