If your Google Shopping ROAS has been jumping around for reasons you cannot explain, the cause is probably not sitting inside your account. It is an auction shaken by a mega-spender. Temu reportedly cut its US digital ad spend by more than 50% in March on tariff news, causing roughly 40% week-over-week CPC swings in key Google Shopping categories (Nova Analytics, Apr 14, 2026, needs primary-source verification). The right response is a cpc strategy built to expect that volatility, not one that panics at it. This post explains what happened and how to stay steady.
What reportedly happened
According to Nova Analytics, Temu cut its US digital ad spend by more than 50% in March, reportedly reacting to tariff news. The reported knock-on effect was roughly 40% week-over-week swings in cost per click across key Google Shopping categories (Nova Analytics, Apr 14, 2026, needs primary-source verification).
One note on the source: this figure is reported and flagged for primary-source verification, so treat the exact numbers as directional. The pattern it describes, though, is one every paid-media operator recognizes.
Why one advertiser can move your CPCs
Google Shopping runs on auctions. Your cost per click is set by how many advertisers are bidding on the same impressions and how hard they are bidding. When a very large advertiser is active, they raise the floor for everyone. When they pull out, competition drops and costs can fall fast. When they return, costs spike again.
That is the mechanism behind the swings. Your CPCs are riding someone else's budget decisions. A category can feel expensive one week and cheap the next without you changing a single setting. Understanding this is the foundation of a sound cpc strategy, whether on Google Shopping or with cpc on Amazon, because both run on auction dynamics you do not fully control.
The mistake that makes it worse
Here is the instinct to resist. When ROAS swings, most advertisers assume the problem is their account and start tearing campaigns apart. That is exactly the wrong move when the real driver is external.
If you rip up a structure that was working to chase a swing caused by a mega-spender moving in and out, you break what was fine. Now you have two problems: the external volatility you cannot control, and self-inflicted damage from over-tinkering. The fix is not more manual changes. It is a system that expects volatility and rides it.
The CPC strategy that stays stable
Build for auction turbulence instead of pretending it will not happen.
Move off rigid fixed-budget forecasting
Fixed-budget forecasting assumes stable CPCs. When a mega-spender swings costs 40% week over week, those forecasts break. Plan in ranges and expect variance rather than betting on a single number.
Use flexible bidding
Let bidding adjust to live auction conditions instead of locking rigid manual bids that get stranded when the auction shifts. Flexible bidding responds to the swing so you are not caught paying yesterday's price in today's auction.
Track ROAS weekly, not daily
Daily numbers will look chaotic during a volatile stretch, which tempts overreaction. A weekly ROAS review lets you separate a real trend from noise and respond to what is actually happening.
Separate signal from noise before acting
Before you change anything, ask whether the swing is your account or the auction. If category-wide CPCs moved, the answer is usually the auction, and the right move is patience plus flexible bidding, not a rebuild.
Where this fits in paid media
Steady paid media is one lever inside a coordinated growth plan. Our teams help brands scale on Amazon, build channels on TikTok Shop, and run paid media through a growth retainer so external volatility does not turn into panic decisions.