---
title: "Equal Loan Payments Calculator"
type: "article"
slug: "equal-loan-payments-calculator"
url: "http://localhost/article/equal-loan-payments-calculator/"
markdown_url: "http://localhost/article/equal-loan-payments-calculator.md"
published_at: "2026-01-20T20:44:51+00:00"
modified_at: "2026-01-20T20:44:52+00:00"
featured_image:
  url: "http://localhost/wp-content/uploads/2022/04/20230809-041332.jpg"
excerpt: "This program is based on one written by Ward Seguin in the March \"85 CATS for the 2068. It had an accuracy problem which I finally blamed on the combination of many iterations in the exponential calculation and the short word length used to store real numbers. This problem was shared in all programs for…"
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model:
  - name: "Sinclair QL"
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    taxonomy: "model"
    url: "http://localhost/model/sinclair-ql/"
indiv:
  - name: "Duane Parker"
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    url: "http://localhost/indiv/duane-parker/"
publication_r:
  id: 35941
  title: "CATS Newsletter"
  type: "periodical"
  url: "http://localhost/periodical/cats-newsletter/"
authors_r:
  - name: "Duane Parker"
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    taxonomy: "indiv"
    url: "http://localhost/indiv/duane-parker/"
volume: "7"
issue: "6"
issues_articles:
  - id: 38899
    title: "CATS v7 n6"
    type: "issue"
    url: "http://localhost/issue/cats-v7-n6/"
pages: "4"
pubdate: "October 1989"
archive_link: false
---

# Equal Loan Payments Calculator

This program is based on one written by [Ward Seguin](http://localhost/indiv/ward-seguin/) in the March “85 CATS for the 2068. It had an accuracy problem which I finally blamed on the combination of many iterations in the exponential calculation and the short word length used to store real numbers. This problem was shared in all programs for personal computers that I could check. I found that substitution of a logarithmic series both solved the accuracy problem and speeded the calculation. Increasing the length of the series increases the accuracy. I also revised the program to make annual totals available whatever the loan start month. It is now in QL basic but conversion to any other basic should not be difficult. Enjoy