This is a 3-3-3 corrective wave pattern forming. Looks like we had 3 strong down waves in 'W'; 3 smaller up waves today for an 'X';
The 'Y' should start very soon, will likely open with a gap down and should carry index to near same decline as 'W' or ~520 points to 24818.
I do not see an ABC pattern here, as there are no 5 wave impulses in the W or X waves.
As always I am not an investment advisor, and this is not advice, it's for education and amusement. Good luck!