2 quick tricks with numbers — helpful in KiwiSaver, property, managed funds

Rule of 72 tells you:

  • How long for lump sum investment to double.
  • If lump sum investment has doubled, what annual return you got.

Dollar cost averaging:

  • A big plus of regular investing.
  • Using it if you have a lump sum.

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Mary Holm, ONZM, is a freelance journalist, a seminar presenter and a bestselling author on personal finance. She is a director of Financial Services Complaints Ltd (FSCL) and a former director of the Financial Markets Authority. Her opinions are personal, and do not reflect the position of any organisation in which she holds office. Mary’s advice is of a general nature, and she is not responsible for any loss that any reader may suffer from following it. Send questions to [email protected] or click here. Letters should not exceed 200 words. We won’t publish your name. Please provide a (preferably daytime) phone number. Unfortunately, Mary cannot answer all questions, correspond directly with readers, or give financial advice.