Run the tester over the specified range of years. Available data
runs from 1986 through 2012 for most screens. You may start at any
month of the year, but other than January can only run through 2011/2012.
Stocks are picked from the screens every holding period (between
1 and 120 months) and held for that period.
Instead of selecting from the available screens, you may choose to
enter codes from any of the backtesters to create hybrid
tests. Simply copy the link listed at the top of a run & paste into the form.
Also see the backtester code guide.
Start with an initial investment. You may also add more
money periodically. You can also subtract from the portfolio by adding a
Instead of adding or subtracting a fixed amount, you can elect to keep the
portfolio at a fixed allocation. This is useful for testing costs
without considering the effects of compounded growth, to see what your money
might do this year.
Normally, the stocks held in a screen are rebalanced on every trade.
You can also specify to never rebalance, which may allow one stock to dominate
a screen as it grows, or rebalance at a fixed interval (which must be a
multiple of the holding period).
You can pay a fixed commission (which is applied to every buy and
sell) as well as a percentage spread (half applied on buy, half on
Capital-gains taxes can be applied, both short-term and
long-term. Taxes may be taken out on every trade, quarterly, or
Screen rankings come out on Friday, and backtests are typically done with
the closing prices on the next Monday, one day after the rankings.
This lag between ranking and trading can be varied from zero days (trade on
Friday) and upward.
Enter each screen to include in the blend, the percentage of the
portfolio to allocate to that screen, and the holding period and
ranks for the screen.
The component screens may have different holding periods; there is no
single holding period for the blend itself. The years and start month of the
blend will be used for all screens, regardless of what is specified for any
If the trading simulator is being used, the rebalancing of the blend
may be specified. By default, the allocation of the blend to its component
screens is reset every year. You may specify any other time period, or
always rebalance (i.e. every month), or never rebalance, allowing
better-performing screens to dominate the portfolio. Only those screens which
are trading on a given month will be brought into balance in the blend for that