ARTICLE SYNOPSIS ...Volume Called the Market by R. Stuart Thomson By going back to October 1986 we can better understand the market explosion that occurred in January 1987, thanks to our cumulative volume (CV) charts. (See ""Cumulative Volume"" in the June 1986 issue of Stocks & Commodities.) Starting in October 1986 and with some slow-down in December as the impact of the new Tax Reform Act reared its ugly head, the technical picture steadily improved. Figure 1 shows how the Dow Jones Industrials' cumulative volume broke out to a new high in September 1986, quickly retreated to a higher low that same month, br...