After a significant drop in June, the Accountants Confidence Index rebounded significantly in July.

The ACI, published in partnership with ADP, is a monthly economic indicator that leverages the insights of accountants into the strength and prospects of businesses in the U.S. The 3-Month ACI skyrocketed to 56.27, up from the previous month's 44.24 -- and well above the 50 mark that separates expectations of growth from expectations of contraction. The 6-Month ACI, meanwhile, came in at 57.53, up from last month's 50.62.

It was by far the biggest jump since the ACI began in 2011, and the volatility reflects the uncertainty in Washington, and concerns regarding the future of tax reform and potential changes in health care.

The ACI is created from a monthly poll of the Accounting Today Executive Research Council, an online community of more than 1,500 tax and accounting professionals.