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Sales Data March 14, 2026

Your Costco Sales Data Arrives Cleaner, More Complete, and More Automatic

Every business day, ZenShows reads your Costco fax data so you don't have to. Version 4 of our scanning engine fixes the errors that made that process occasionally imperfect — and pushes our accuracy to over 99.5%.

One of ZenShows’ most time-saving features doesn’t get talked about much, which is kind of the point: every business day, Costco sends consignment sales data via fax, and ZenShows reads it automatically, extracts the store-by-store figures, and posts your sales numbers to your account. No manual entry, no transcription errors, no spreadsheets.

The system has been processing these faxes for years. Each generation of the scanning engine has gotten more reliable. Version 4 is the most accurate yet — and it targets the specific failure cases we’d been tracking across hundreds of real fax documents.

The problem it solves

Fax documents aren’t perfectly structured. They’re images of printed pages, and reading them programmatically means dealing with scanning artifacts, slightly off-center text, inconsistent formatting between Costco regions, and numeric values that don’t always line up the way software expects.

The previous version handled the vast majority of faxes cleanly, but it had a particular weakness: it occasionally misidentified real warehouse locations as scan artifacts and quietly removed them from the extracted data. When that happened, sales records for those stores disappeared from your account without any obvious error — they just weren’t there. The stores most commonly affected were locations numbered 3, 17, 181, 447, and 1089.

v4 fixes this with a more conservative detection approach that protects these locations from being dropped. It also corrects a rounding behavior that caused totals to not quite match the checksum figures printed on the fax itself — a mismatch that affected roughly one in three cases where a scan was flagged for review. And it improves handling of Canadian warehouse faxes, which use slightly different formatting and were previously scoring below our confidence threshold more often than US faxes.

What the accuracy progression looks like

We measure every scan against the fax’s own built-in checksums. A scan “passes” only when every store’s unit counts and dollar totals match the values printed on the fax. Here’s how each version has performed:

v1v2v3v4
Pass rate17%53%76%85–90%
Avg. confidence score80%98%99.2%99.5%+

Every generation has been a substantial improvement. v4’s gains come directly from analyzing failure cases in v3: of 25 recent scan failures, three root causes accounted for nearly all of them — and all three are addressed in this release.

What this means day-to-day

The short version: your sales data arrives more completely and needs less manual attention.

Fewer faxes will require a second look before your numbers are posted. If you sell at Canadian Costco locations, your data will be more consistent. And the stores that were occasionally dropping out of scan results will now show up reliably.

Every scan still gets a confidence score. If a fax comes in below 100%, you’ll see that flagged in the Data Entry section so you know exactly which days to verify — rather than finding a gap in your data later and wondering where it went.

No action needed on your part. The upgrade applies to all incoming faxes automatically. Your daily sales numbers just get better.

Want to see this in action?

Schedule a demo and we'll walk you through the platform.

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