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diff --git a/node_modules/date-fns/esm/differenceInYears/index.js b/node_modules/date-fns/esm/differenceInYears/index.js
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+import toDate from "../toDate/index.js";
+import differenceInCalendarYears from "../differenceInCalendarYears/index.js";
+import compareAsc from "../compareAsc/index.js";
+import requiredArgs from "../_lib/requiredArgs/index.js";
+/**
+ * @name differenceInYears
+ * @category Year Helpers
+ * @summary Get the number of full years between the given dates.
+ *
+ * @description
+ * Get the number of full years between the given dates.
+ *
+ * @param {Date|Number} dateLeft - the later date
+ * @param {Date|Number} dateRight - the earlier date
+ * @returns {Number} the number of full years
+ * @throws {TypeError} 2 arguments required
+ *
+ * @example
+ * // How many full years are between 31 December 2013 and 11 February 2015?
+ * const result = differenceInYears(new Date(2015, 1, 11), new Date(2013, 11, 31))
+ * //=> 1
+ */
+export default function differenceInYears(dirtyDateLeft, dirtyDateRight) {
+  requiredArgs(2, arguments);
+  var dateLeft = toDate(dirtyDateLeft);
+  var dateRight = toDate(dirtyDateRight);
+  var sign = compareAsc(dateLeft, dateRight);
+  var difference = Math.abs(differenceInCalendarYears(dateLeft, dateRight));
+
+  // Set both dates to a valid leap year for accurate comparison when dealing
+  // with leap days
+  dateLeft.setFullYear(1584);
+  dateRight.setFullYear(1584);
+
+  // Math.abs(diff in full years - diff in calendar years) === 1 if last calendar year is not full
+  // If so, result must be decreased by 1 in absolute value
+  var isLastYearNotFull = compareAsc(dateLeft, dateRight) === -sign;
+  var result = sign * (difference - Number(isLastYearNotFull));
+  // Prevent negative zero
+  return result === 0 ? 0 : result;
+}
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