Working notes
Has demand fallen, or have the rankings slipped?
Fewer clicks do not explain the cause on their own. The next question is which searches changed, not which reassuring explanation sounds best.
The short answer
Compare demand and visibility separately. Fewer clicks can come from fewer searches, weaker rankings or a change in the mix of queries.
Why it matters
A page can receive fewer clicks while its average position holds steady. Another page can lose position while demand remains. Those are different situations, and they should not lead automatically to the same recommendation.
Start with comparable periods
Check the dates, length of the reporting windows and any known seasonal pattern. A peak period and a quieter season can make a simple previous-period comparison misleading.
I'd use the comparison that answers the actual question, and explain its limits rather than switching between periods to find the most flattering number.
Look at pages and queries together
Find where the change is concentrated. Compare the affected pages with the searches that produced their visibility. Look at clicks, impressions, click-through rate and position together.
A whole-site average can hide a change in the mix of queries. A similar average position does not prove that every important query held its ranking.
Treat an explanation as something to test
Lower impressions with stable positions may be consistent with lower demand, but that is not proof on its own. Changes in coverage, query mix and reporting also matter.
Where individual commercial queries have clearly moved backwards, I'd not explain the problem away by calling everything seasonal.
Tell me what you need to sort out
If you need this checked or fixed on a real site, send me the URL, a safe example and what you are trying to achieve.
Connect the diagnosis to the next job
A ranking issue may need a closer look at the page and its competition. A change in product demand may call for supporting newer products or better alternatives. Some situations need both.
My reporting approach is about making those distinctions. Measuring the useful result matters just as much as diagnosing the traffic chart.
HAVE SOMETHING AWKWARD?
Tell me what you need to sort out
Send me the URL, what is happening, what you have already tried and what a useful result would look like. A small anonymised sample is enough to start - do not send passwords, credentials or sensitive customer data.