S&P500 or $SPX or ^GSPC is waiting for some triggers that are not in sight in the near future. Until then it would be just a lacklustre trade with some volatility caused by economic data from time to time. Notable this week would be:-
1. Existing Home sales on the 23rd
2. FED rate, Durable goods order, New homes on 24th,
3. Personal consumption, GDP and Jobless claims on the 25th

Unlike DOW, this index has managed to trade above its 50days and 200days SMAs continuously. Both these moving averages are intending to crossover, is a good sign. Medium to Long term investors may stay sanguine as long as this index does not trade continuously below these averages. Just whipsawing these averages should not be the cause of worry for investors until 845 is holding.
For short term traders, the immediate resistances are at 930 and 936. A move above the second resistance is needed to surpass the recent high of 956.
Short term supports are at 903.8 and 888.8. Only a close below the second support would be a signal to prepare for another bout of downtrend in Medium term.
The support at 845 should lend strong support for long term investors.
Non-trending markets are suitable for ‘non-directional’ options strategies.