traffic-drop

Traffic drop investigation

A drop is a claim to test, not a fact to explain. Most "drops" are robots, calendar effects, a broken counter or one segment — find which before naming a cause. Work through the steps in order and stop as soon as the evidence answers the question.

0. Know your sources

• Metrica tools (run_comparison, run_timeseries, run_report, describe_counter) are required. Without them, say so and stop.
• Webmaster tools (get_hosts, get_indexing, search_queries, …) are optional. If they are not available, do the Metrica steps, then list the search hypotheses you could not check and how the user can check them (install the yandex-webmaster-mcp plugin, or look in Webmaster: Indexing → Pages in search, Diagnostics).
• If a metrica-hygiene or webmaster-audit skill is available, its rules apply here too.

1. Confirm the drop

• run_comparison of the period in question (B) against a baseline (A) of the same length and weekday mix, both complete (end yesterday or earlier), filtersA/filtersB = ym:s:isRobot=='No', metrics ym:s:visits, ym:s:users.
• Also compare the same weeks a year back (shift by 364 days) when the baseline might be seasonal (holidays, summer, New Year).
• Give absolute numbers. If the change is within noise (a few percent, or a small base), say there is no real drop and stop. If the unfiltered drop is large but people are flat, it was robots — say so and stop.

2. Date it

run_timeseries daily over ~6 weeks (robots excluded). A step on one day points to a release, a tracking change or a search event; a slope points to rankings, demand or seasonality. Note the first day of the change.

3. Find where it is

Break the comparison down one dimension at a time and compute each row's share of the total delta (row delta / total delta):

1. ym:s:lastsignTrafficSource — which source moved;
2. inside that source: ym:s:lastsignSearchEngineRoot for search, ym:s:lastsignUTMSource/ym:s:lastsignUTMCampaign for ads, ym:s:referer for links;
3. ym:s:startURLPath (landing page) — which pages lost entries;
4. ym:s:deviceCategory, ym:s:regionCountryName if still unclear.