Even though the High-Low Percent indicators for small-caps and mid-caps are dragging their feet, both indexes are recording more new highs than new lows here in September. Chartists can also use the High-Low Line to measure the high-low differential. The chart below shows the High-Low Lines for the S&P 500, S&P 400 MidCap Index and S&P 600 SmallCap Index. All three turned up in September and are above their 10-day EMAs. These indicators should be considered bullish until they turn down and break below their 10-day EMAs.