“The Russell 3000 tracks the performance of the 3000 largest US traded stocks which represents about 98% of all US incorporated equity securities” Source – Google.

Essentially that means the Russell 3000 is a fair representation of the US stock market, so if the advance is close to ending 5 waves to complete an impulse wave from its 2016 low, then there is a strong chance that a decline on the Russell 3000 will coincide with a decline on other US stock markets.

Overlaying the Russell 3000 with the SPX gives us a near perfect match, so in a nutshell; the Russell 3000 and SPX are one and the same market. The current advance appears to be in the late stages of wave [5] of an impulse wave from the 2016 low. When wave [5] finally does complete, a significant decline would be expected, until we see a big move under 1650 as well as a strong move under 2775 on the SPX, then further upside could still be seen before wave [5] finally completes.