Due-column betting

'Due-column Betting' (also: 'due column betting') is a type of fixed-profit betting strategy whereby a bettor increases the amount he wagers on a single proposition after each successive loss. According to this system, the bettor determines a target profit before he begins betting. Then he increases his bet on propositions following a loss in such a way that a win will recover the sum of all amounts he lost from his preceding bets plus gain him his predetermined profit.

While similar to both the Martingale and Labouchere strategies, "Due-column betting" differs from other like betting systems in that it accounts for the odds variance in successive parimutuel propositions. Still, it is often used interchangeably with the casino gambling term "progressive system", which refers to several similar betting systems typically employed at casino gaming tables.

Due-column wagering is considered a fixed-profit system because the Due-column bettor determines his desired profit before he begins betting. However, whereas with percentage-based money-management systems the bettor varies his bets as a percentage of his bankroll, with a series of Due-column bets he bets the amount necessary to make his desired profit plus the total amount necessary to recuperate what he has lost in all previous wagers.

Supposedly betting this way ensures that if the bettor correctly calls a single race at any point in the series he will have profited and can cease betting or begin a new series. Proponents of the system argue that the probability of experiencing ten consecutive losses if the bettor is an average, 33 percent handicapper is 1.82 percent. Consequently, they conclude, a Due-column bettor has a given probability of profiting from slightly more than 98 percent of all 10-race series. And, they therefore believe, a Due-column bettor will win the product of his designated profit times the expected percentage of wins per the number of series played; or, assuming the bettor's desired profit is $100, he will win about $9,800 per 100 series played.

The coining of "Due-column" is due to bettors' creating charts to track their bets. A typical Due-column chart is as follows:

There are several problems with the assumptions that Due-column bettors make, not the least of which is that the mathematical basis for the system is flawed. The average bettor in any series of horse races is a 33 percent handicapper with an average mutuel of $5.00. Such a bettor's mathematical expectation can be expressed as follows:

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