For River Murray irrigators, one number underpins their crops, their businesses and their livelihoods: the one ending in a percentage sign announced in the lead-up to July 1 each year.
The opening water allocation decided upon by the state government determines how much irrigators will be able to take from the river each year, up to a maximum of 100 per cent of their entitlements.
In years gone by, the opening allocation would be announced on or around the first day of the financial year, giving irrigators no warning of a cut that could potentially destroy their businesses.
That practice came under heavy scrutiny in 2016, when a footnote in a Department of Environment, Water and Natural Resources newsletter in February was the first warning of what turned out to be a 64pc allocation cut.
Now, the department has proposed a new system.
A minimum allocation would be announced in mid-April each year, accompanied by a table showing the probability of higher allocations.
A final allocation would be announced on June 15.
If available, allocations carried over from previous years would be calculated in August and September and granted by October 31.
The department is currently seeking public feedback on the idea.
It will produce a revised plan by November and publish it in January, with the intention of introducing the new system ahead of the 2019-20 water year.
South Australia is entitled to 1850 gigalitres of water each year.