I have explained impression share to accountants using PowerPoint decks, Loom videos, Google Slides with animations, audio presentations, and at one particularly desperate point, a full-scale musical adaptation set to the songs of Oklahoma.

I am not joking. I wrote lyrics.

"Oh, the CTR is climbin' and the auction's feelin' fair, when your campaign finally captures ninety percent impression share."

They listened politely. They nodded. Then one of them asked if we could just pause the ads on slower days to save money.

I have counted. Eighty percent of the grey hair in my beard is impression share conversations.

So let me try one more time. For every marketer who has ever sat across a conference table from someone with a spreadsheet and a soul made of amortization schedules. Here is the marketing math that matters, translated into a language that accountants might actually accept.

Impression share is not a vanity metric. It is a competitive position metric.

Here is the analogy that works best.

Imagine your company has a retail location on the busiest street in your city. Every day, ten thousand people walk past that street. Impression share tells you what percentage of those people actually saw your store.

If your impression share is 40%, six thousand people walked past and never saw you. Not because you had a bad product. Not because your price was wrong. Because you were not visible when they were looking.

Now here is the part that makes accountants uncomfortable.

The people who walked past and did not see you did not disappear. They saw your competitor instead.

Impression share lost to budget means you had the right to be visible and chose not to be. Every point of impression share you leave on the table is a door you closed on a potential customer, not because they rejected you, but because you were not there.

Why spend is not a tap.

Accountants love the tap metaphor. Turn it up when you need revenue. Turn it down when you do not. Clean. Controllable. Logical.

Here is why it does not work that way.

Google and Meta run auction systems. Your position in those auctions is determined by your bid, your quality, and your consistency. When you cut spend suddenly, three things happen that do not reverse cleanly when you turn it back on.

First, your Quality Score drops. Google's algorithm interprets inconsistent spend as a signal that your ads are less relevant. Lower quality means higher costs per click when you return.

Second, your audience signals reset. The platforms spend your first weeks of budget learning who converts for you. Cut and restart and you are paying for that education again.

Third, your competitors fill the gap. They were watching your impression share. The moment you stepped back they stepped forward and some of those customers made a decision while you were gone.

Turning the tap off is not free. It has a cost that does not appear on the invoice.

The three numbers your finance team should actually care about.

Stop trying to explain CTR, impression share, and Quality Score in isolation. Connect them to numbers that already live in their world.

Blended CAC. Total marketing spend divided by total new customers acquired. This is the number that belongs in a finance meeting. Not cost per click. Not CPM. Blended CAC. It speaks their language and it forces the right conversation about efficiency across the whole system, not just one channel.

Payback period. How many months until a new customer's revenue covers the cost of acquiring them. Finance people understand payback periods. They use them for capital expenditure decisions. Marketing spend is a capital expenditure. Start treating it like one in the room.

LTV to CAC ratio. If your average customer is worth three dollars for every one dollar you spent acquiring them, you have a machine worth feeding. If that ratio is below two, you have a problem worth fixing before you talk about impression share at all.

Lead with these three. Build everything else as supporting evidence.

The accountants were not wrong to ask hard questions. They were wrong to think the answers would be simple.

Marketing spend is not a tap. It is infrastructure. You do not turn off the electricity in a factory on slow days and expect the machines to restart at full speed on Monday morning.

The goal of every conversation with finance is not to win the argument. It is to build a shared language where the right decisions can actually get made.

I am still working on the musical. The second act needs work.

Rob

P.S. If someone in your finance team is genuinely trying to understand this stuff, send them this. Not as a gotcha. As a resource. The best finance partners I have ever worked with were the ones who asked hard questions and actually wanted real answers.