Calendar Rebalancing
Calendar rebalancing is the most rudimentary rebalancing approach. This strategy simply involves analyzing the investment holdings within the portfolio at predetermined time intervals and adjusting to the original allocation at a desired frequency. Monthly and quarterly assessments are typically preferred because weekly rebalancing would be overly expensive while a yearly approach would allow for too much intermediate portfolio drift. The ideal frequency of rebalancing must be determined based on time constraints, transaction costs and allowable drift.
A major advantage of calendar rebalancing over formulaic rebalancing is that it is significantly less time consuming for the investor since the latter method is a continuous process.