second shipment, page-18

If anyone is interested , these are the numbers that are causing me concern.
1 Train load approx 7,000 t
1 ship load approx 60,000 t
5 ships per week for one year would move 5 x 60000 x 52 = 15,600,000 which is close to target.
So the problem I have is how many trains @ 7,000 t can be run per day.
5 shiploads p/wk = 300,000 t = 40 + trains per week ???
Hopefully I have made an error and continually make the same error each time I check the numbers.
Anyone ?