Adding a rich calendar of holidays, earnings, macro-economic release dates and times, ex-dividend payouts, "last week of <month>" would allow searching and backtesting for stocks that have consistent behavior surrounding these events (e.g. Search for stocks that trend upward for the week each year prior to "US Thanksgiving" or "Good Friday", or stocks that drop and recover share price within 5 days of ex-dividend date or go up in the afternoon when "New Home Sales" are reported positively in the morning). Allow these event markers to be stop criteria as well.