Subject to some differences in language and timeframes, the key provisions of the
price revision clauses are broadly similar across contracts: Most price revision
clauses refer to changes which have taken place between the effective date of price revision and the effective date of the previous price revision, or the initial
contract price. The occurrence of such changes will allow one or the other party to
request an adjustment of the price. The changes which are pertinent are those
which have resulted in a divergence between the obtainable end-user market value
for gas and the contract price formula. The adjustment should effectively reset the
commercial balance between the parties. This commercial balance is the combina-
tion of the price risk (a maximum market value - **minus) on one side, coupled
with the volume risk (a cash flow guarantee) and a reasonable margin on the
other side. Both parties can ask for a review, and review is generally only possible
once every 3 years

Не могу понять, что здесь означает "minus"

Спасибо за помощь!