Incorporating a spread into a backtest

[spacebalts67]

I would like to know how to incorporate a spread into backtesting a forex strategy. How does this calculate? Would it just take, say 3 ticks off the end of each trade?

[NinjaTrader_Ray]

Add 3 ticks slippage when runnign your backtest. Slippage is a parameter you can set in the stragegy dialog window when running a backtest.