A select passage from that link:
"They estimate that land-based insects, which make up the majority of species, have been declining at nearly 1% per year, or almost 9% per decade. But during the same period, the small proportion of insects which live in freshwater experienced a 1% annual increase, or just over 11% per decade.
Does this give us cause to be relatively cheerful (or at least, less miserable)? Hardly."
There's obviously a lot more going on in that link, including a link to the actual study. I'd be cautious about thinking it's just about "how they interpret the numbers." Kind of like a snowball in Congress.