"impact declined" is correct and usable in written English.
You can use it to indicate that the effect or influence of something has reduced. For example: The factory closure had a significant impact on the local economy, but as time went on, the impact declined.
But his inventiveness increased as its impact declined, in riffs on furniture that became phantasmagorical.
As expected, subsidy impact declined as deposition distance increased.
Consistent to previous studies, the impact of MSCs on mFB phenotype was prominent within a short distance of separation (Fig. 3F) and the impact declined to comparable level as control (mono-cultured mFBs).
When the Galaxy went on the road, every team saw significant boosts in attendance when Beckham played - although that impact declined last year.
Amphibians are good indicators of human impact, declining steadily worldwide.
The impact declines steadily such that for the decile of firms with the highest wages, the impact is 0.6percentt.
In this Chinese study population, a significant, decreasing trend in AAM persisted, even after adjustment for rural/urban region, education level, and age at registration in the PHCSS, suggesting that other factors beyond these impact declining AAM.
This impact declines as the increase in HIV infectivity and susceptibility becomes smaller; and if HIV infectivity and susceptibility are not altered at all in those with chlamydia infection, then chlamydia has no effect on HIV transmission.
Even with a 1.5°C rise coral reefs would still be severely impacted, declining by 70-90% — but virtually all (>99%) reefs would be lost with a 2°C rise.
For prime-age workers, the negative impact declines to about 3 percentage points.
From Fig. 4a and d, it is noticeably obvious that algal growth was linearly correlated with N supply to a certain level and then show negative impact (decline).
