WASHINGTON — The American Chemistry Council (ACC) Chemical Activity Barometer (CAB) — a leading economic indicator — showed a 0.2 percent gain in November. The gain follows an upward revision of October’s data, which showed zero growth, as measured on a 3-month moving average (3MMA). However, the CAB remains up 3.7 percent over November 2013. The CAB is based on production, equity prices, product prices, and inventories and other indicators. Chemical industry activity has been found to consistently lead the US economy’s business cycle because of its early position in the supply chain. ACC, Washington, is an industry trade association for American chemical companies.