I have 5 lots "in transit". One definitely lost. I have lost recently sendings inland, I dont know what happens.
Regarding the speed, the answer, Marleen, I think is this: if you send faster than you receive, for instance, if you send in one or two days, but the average is 10 days, so, you will accumulate sendings.
If you suddenly stop sending, probably you will have more receptions than sendings in one month or so, but, on the other hand you will have to wait one more month to receive more envelopes.
The conclusion is the system has it´s own speed, no matter your speed is. If you go faster than the average, you will have always deficit, but receive more regularly, if you go slower, in the beggining you will receive more, but after that, the system will balance, and you will receive less. Martine case is she is always sending fast, so, she will always have six sending backwards, if she slows the sendings, she will balance, but she will receive less envelopes in the long term.
It is my impression. Maybe Danubius can explain more...