Looking at the bull market advance since 2009, we can see at least two options for counting. The options are that wave 3 ended in May'15 (blue) or wave 3 is ongoing (green).
The late 2015 decline certainly looks like a potential wave 4 except that the high earlier in May that year came with a negative divergence in RSI. Third waves usually have a strong RSI reading (like now).
If SPX is currently in wave v of 3 (green), then wave v is expected to be 100% or 161.8% of wave 1 (2009-10). As 100% has already been exceeded, 161.8% at 2,700 is the next target.
However, if SPX is in wave 5 from the 2009 low (blue), it is expected to be 61.8% of the 2009-20015 rally. That would target... (drum roll)... 2,700.
Take a "sneak-peek" at Seattle Technical Advisors.com