Predefined Technical scan "bullish 50/200-day MA crossover" returned 38 charts on 7-9-18 at 8:10PM PDT. Of these 38 charts: 3 x on 7-9; 12 x in 1 to 4 day prior; 12 x 5-10 days prior; 3 x 11-20 days prior; 2 x 21 days prior; 6 never x positive on 6 month chart.
Same type of results when create crossover scans on Advanced workbench. I can understand a data delay of a couple days, but to have 29% crossed 2 weeks to never is pretty loose results. Any possible explanation for this? R-Day
It also occurred to me later that you may be getting different results if your own chart style uses exponential moving averages (ema) instead of simple moving averages (sma). The scan is done using sma.