# Classify Accounts by Activity Tier

> The accounts fall into tiers. Where is the cutoff?

Canonical URL: <https://datadriven.io/problems/classify_accounts_by_activity_tier>

Domain: SQL · Difficulty: hard · Seniority: L4

## Problem

An SRE flagged a latency outlier. Find the highest latency value that appears at most twice across all API calls. First identify latency values that occur once or twice, then find the maximum among those.

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