S corporations now account for two-thirds of U.S. corporate tax returns (see NTA report) and while designed for simplicity, they’ve become increasingly complex and harder for regulators to standardize and monitor.
As the number of small businesses has exploded, the number of S corporations formed has more than quadrupled since the last review (of 1984 returns) while the number with assets exceeding $10 million has increased 10-fold. Today’s S corporations are not necessarily small, and not necessarily easy to classify for tax reporting purposes.