Beginning 1993:Q1, unadjusted flow from the FR Board, Capital Markets Section, on the basis of bond data from SDC and medium-term notes (MTN) issues from DTCC Series is equal to Capital Markets' weekly internal report on Nonfinancial Corporate Bond Issuance, column Net Issuance. Level is obtained by adding flow to preceding level; data for the most recent ten years show no significant seasonality.