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diff --git a/src/mongo/db/query/query_stats/aggregated_metric.h b/src/mongo/db/query/query_stats/aggregated_metric.h
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+/**
+ *    Copyright (C) 2023-present MongoDB, Inc.
+ *
+ *    This program is free software: you can redistribute it and/or modify
+ *    it under the terms of the Server Side Public License, version 1,
+ *    as published by MongoDB, Inc.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    Server Side Public License for more details.
+ *
+ *    You should have received a copy of the Server Side Public License
+ *    along with this program. If not, see
+ *    <http://www.mongodb.com/licensing/server-side-public-license>.
+ *
+ *    As a special exception, the copyright holders give permission to link the
+ *    code of portions of this program with the OpenSSL library under certain
+ *    conditions as described in each individual source file and distribute
+ *    linked combinations including the program with the OpenSSL library. You
+ *    must comply with the Server Side Public License in all respects for
+ *    all of the code used other than as permitted herein. If you modify file(s)
+ *    with this exception, you may extend this exception to your version of the
+ *    file(s), but you are not obligated to do so. If you do not wish to do so,
+ *    delete this exception statement from your version. If you delete this
+ *    exception statement from all source files in the program, then also delete
+ *    it in the license file.
+ */
+
+#pragma once
+
+#include <algorithm>
+#include <cstdint>
+
+#include "mongo/base/string_data.h"
+#include "mongo/bson/bsonobjbuilder.h"
+#include "mongo/platform/decimal128.h"
+
+namespace mongo::query_stats {
+
+/**
+ * An aggregated metric stores a compressed view of data. It balances the loss of information
+ * with the reduction in required storage.
+ */
+struct AggregatedMetric {
+
+    /**
+     * Aggregate an observed value into the metric.
+     */
+    void aggregate(uint64_t val) {
+        sum += val;
+        max = std::max(val, max);
+        min = std::min(val, min);
+        sumOfSquares = sumOfSquares.add(Decimal128(val).multiply(Decimal128(val)));
+    }
+
+    void appendTo(BSONObjBuilder& builder, const StringData& fieldName) const {
+        BSONObjBuilder metricsBuilder = builder.subobjStart(fieldName);
+        metricsBuilder.append("sum", (long long)sum);
+        metricsBuilder.append("max", (long long)max);
+        metricsBuilder.append("min", (long long)min);
+        metricsBuilder.append("sumOfSquares", sumOfSquares);
+        metricsBuilder.done();
+    }
+
+    uint64_t sum = 0;
+    // Default to the _signed_ maximum (which fits in unsigned range) because we cast to
+    // BSONNumeric when serializing.
+    uint64_t min = (uint64_t)std::numeric_limits<int64_t>::max;
+    uint64_t max = 0;
+
+    /**
+     * The sum of squares along with (an externally stored) count will allow us to compute the
+     * variance/stddev.
+     */
+    Decimal128 sumOfSquares{};
+};
+
+}  // namespace mongo::query_stats