MINYANVILLE ORIGINAL With everyone talking sell-off we thought now would be a good time to update our top 20 strongest S&P 500 (INDEXSP:.INX) names. One name that has been on the list for a couple of weeks made new highs yesterday: American Tower Corporation (NYSE:AMT). If you had gotten long these names when we moved to a Strong Buy you would be up 41.25% vs. the S&P 500’s 12.40%.  The average duration for these 20 names is 69 days.  Names showing strength today are: Airgas (NYSE:ARG) Leggett & Platt (NYSE:LEG) Ameriprise Financial (NYSE:AMP) and Equifax (NYSE:EFX).  Note that 85% of ...