In your very last clause, is this one value (if so, then it's okay as is) or do you mean each of these to be separate values? Then it should be:
{PershingTrades.SecType} = "8" and
{PershingTrades.SecMod} in ["C","P","E","B","D","L","M","S","T"]
You need to put the entire list of or statements within () so the formula doesn't read it as select the date by parameter OR (type = "8" and mod = "0"), etc. So it should look like:
{PershingTrades.TradeDate} = {?Trade Date Range} and
{@Random Number} <= 0.10 and
not ({PershingTrades.Symbol} like "") and
(
(
{PershingTrades.SecType} = "1" and
{PershingTrades.SecMod} = "0"
)or
(
{PershingTrades.SecType} = "2" and
{PershingTrades.SecMod} = "0"
)or
(
{PershingTrades.SecType} = "2" and
{PershingTrades.SecMod} = "1"
)or
(
{PershingTrades.SecType} = "3" and
{PershingTrades.SecMod} = "0"
)or
(
{PershingTrades.SecType} = "3" and
{PershingTrades.SecMod} = "1"
)or
(
{PershingTrades.SecType} = "4" and
{PershingTrades.SecMod} = "0"
)or
(
{PershingTrades.SecType} = "9" and
{PershingTrades.SecMod} = "0"
)or
(
{PershingTrades.SecType} = "8" and
{PershingTrades.SecMod} in ["C","P","E","B","D","L","M","S","T"]
)
)
...except I'm not sure what the last clause should be--only you know that.
-LB