The Biotech sector has the greatest prospect in the 25 to 28 day period. The estimated best ETF in that sector for the mentioned period is $BIB.
On the sell side, the Real Estate sector has the worst outlook in the 21 to 24 day period; in this sector, $IYR may have the lowest results.
Six weeks ago, I suggested the Emerging Markets and Commodity Sectors.
$EEM - since Jan 20th
$DBC - since Jan 20th.