findLastNotAfter(key) {
		const values = this._values;

		for (let index = key; index >= 0; index--) {
			const value = values[index];

			if (value) {
				return value;
			}
		}
		return void 0;
	}
Finds the value of the entry with the largest key less than or equal to the provided key
@param {number} key The provided key
@returns {*|undefined} The value of the found entry, or undefined if no such entry exists.