For the individual contributer, the iStock figures are still worrying, as the gradual growth in visits is nothing like in proportion to the growth of files contributed.
For many, many years the average number of downloads per file per month has been dropping. Anyone with a long set of personal data can see that.
But now the compensating factors of cannister level jumps and rising prices leading to rising commission payments have been taken out of the equation.
One thing about these data services is that they measure whatever it is they are measuring impartially so the changes they record are real. Whether it is possible to interpret them in a meaningful way is another matter as is the question of whether their access to data has some systematic bias built in.
It's also worth noting that even if the number of buyers visiting were constant, it would say nothing about whether their budgets were increasing or decreasing and whether they were putting it all into one or two agency files when in the past they might have bought a dozen contributors files. The diversion of iStock income to Agency must do significant damage to contributor earnings.