Ann: Appendix 4D and Half Yearly Report and Accounts, page-14

Oh wow, yeah we're blitzing through it now with the tin price where it is.

Dec '22 to Dec '23 took us from $38.5M to $26.3M, so a $12.2M drop in a year.
Dec '23 to Jun '24 took us from $26.3M to $14.7M, so an $11.6M drop in six months!

As for whether or not we can recognise more from the $156M chunk, I've been trying and failing to find this out recently. My current understanding is that there were a couple of large recognised chunks several years ago down from the unrecognised $254.2M (yr to Jul 2021: $25.5M, and yr to Jul 2022: $82.3M) but the unrecognised $156M loss bundle subject to a restricted rate of utilisation has always been listed as that distinct $156M, so burning the other bundles down doesn't necessarily tell us what happens with the remaining bit.

https://classic.austlii.edu.au/au/legis/cth/bill_em/nbtsb12002471/memo1.html
The above link, chapter 8, seems to deal with this topic, although it's pretty dry reading

My basic understanding of it would be that the bundles from 254->156 were able to be tied very directly to MetalsX the "Company" / "Parent" while the 156->0 bundle(s) relate to other portions of the consolidated group. Rate of utilization would seemingly then be possible for MetalsX to use, but tied to the expected utilization rate of that member of the group, which is a little difficult to understand when we're talking about something like an undeveloped copper mine or nickel mine... If their rate of utilization would be ($0/yr profit = $0/yr) that might mean those $156M are trapped, but it seems very odd that we would hang on to these losses but have our use of them dependent on whether some now-unrelated company starts selling product or not.

My actual conclusion is that I'm not an accountant or finance lawyer so you should have stopped reading after "chapter 8 seems to deal with this topic" as that's about the last thing I said I have any level of confidence in but maybe someone with a bit more experience in these matters can weigh in. In particular I think this isn't an unusual situation for big miners as while searching "restricted rate of utilisation" only gets MLX results, "rate of utilisation" w/r/t losses does bring up other companies like Glencore discussing the same thing in the same part of their reports