! Rules to see if an ER fired. If it did, rub out the ScanAny date
side effect by place ResetDate's on the end of the rule.
UpER6days if ScanAny(UpER,scandays) and ResetDate().
DnER6days if ScanAny(DownER,scandays) and ResetDate().
MultiERs if ratio <> 0.
UpER if [er up] >= erupval.
DownER if [er down] >= erdnval.
CntUps is CountOf(UpER,scandays).
CntDowns is CountOf(DownER,scandays).
ratio is CntUps/CntDowns.