>> The 7 bead one pictured in the article header is slower to work with (classic suanpan) When I was growing up in the early seventies, my dad still occasional

>> The 7 bead one pictured in the article header is slower to work with (classic suanpan) When I was growing up in the early seventies, my dad still occasionally used a suanpan to do calculations for his business. As printing calculators got cheaper, it eventually got retired (I have it now, but don't use it) but he did teach me how to use it. It does not take very long to get good/fast at using it, at least for stuff like adding up a pile of receipts.