I found these results particularly interesting, as nearly none of the ETFs I expected are present. The following were my most interesting observations:
1. Japan seems to rank consistently well, with DND and DFJ taking 1-period and 17-period.
2. The overall best absolute correlation in this lag-range is found in the 21-day lag with the S&P Global Consumer Discretionary fund.
3. Correlations around multiples of 5 seem to be stronger, representing weekly periodicity as expected.
4. The Double Dow Inverse DXD ranks best in the 6-period lag.
5. The most common type of fund is "high income," something I am somewhat at a loss to explain.