Your comment about 1rail loosing business on the Darwin to Adelaide how much have they lost?
I went back and did some Googling.
There doesn't seem to be any definitive data source for freight volumes on the Tarcoola to Darwin line.
The best I could come up with are the Genesee & Wyoming quarterly carload reports which cover the period from when GWA purchased the Freightlink business, commencing at the beginning of 2011, and when the sale of G & W to Brookfield was agreed to in May 2019 and the reporting ceased.
In the carload reports for Australia there is an item for 'Intermodal' which it is fairly safe to assume is nearly all Tarcoola-Darwin line traffic. As best as I can remember between 2011-2019, with one exception, GWA had no other intermodal traffic.
The one exception was the movement of cotton in containers from the Narrabri area. It's hard to know whether that was included in the intermodal figures, or came under agricultural products. The traffic was not that regular so would not impact too strongly on the figures.
The peak year seems to be 2013 when 65148 'units' were carried. In the calendar year 2018 there were 55716 'units' carried which is a decline of around 14.5 per cent.
I take the term 'units' to mean both 20' and 40' units rather than the Australian style of reporting TEUs (20' unit equivalents).
If we take the last quarter reported by G & W - Q1 2018 - and compare it with Q1 2019 the decline for the quarter was 8.25%. If this is projected to the end of 2019, at that rate then the decline between 2013 and 2019 would hypothetically be 21.5%