想知自己夠唔夠錢退休, 自己download jim otar 個retirement calculator, 佢有約100 年既股票/債卷data 去模擬你舊錢係唔同年齡同年份 (1970 年高通脹 vs 1940 年蕭條開始退休可以好唔同), 個組合會唔會捱得住.
http://retirementoptimizer.com/ (free version 淨係可以計55歲退休)
入面可以自己入開支 / 額外通脹率 (on top of historical figure) / 點manage 個portfolio 之類 (e.g. stock / bond allocation)