'to be placed market'

[rogerlisa]

Hello all.
I am currently having a break from trading but that is not stopping me from playing in practive mode. Now excuse my naivety here as no little about bets etc, of which there is obviously a vast amount.
The question I have is simple - in the 'to be placed
market' in horse racing, under each selection there are two black 000 figures. When I place a lay or back bet both of these change obviously, but what is the difference between the two? For instance (baring in mind I am in practice mode) I layed the favourite and it finished the race in 2nd. One of the figures changed to a minus number and the other did not. I am assuming that one of the figures (minus one) was showing what I had lost as the horse came second and the other one was showing what I had won because it did not win the race. Is this correct? Thankyou in advance.