Annual unadjusted flow from BEA, NIPA, Table 6.12D, line 14, Nonfarm proprietors' income: Finance and insurance. Prior to 2001, series was an unpublished estimate provided by BEA. Series is converted to quarterly by dividing the annual unadjusted flow by 4 and applying it to each four quarters. Data for the most recent ten years show no significant seasonality. Series has no levels.