Calculations were carried out using a yupana (Quechua for "counting tool"; see figure) which was still in use after the conquest of Peru.
kˌælkjʊlˈeɪʃənz wɜː kˈæɹid ˈaʊt jˈuːzɪŋ ɐ juːpˈɑːnə kwˈɛtʃjuːə fɔːɹ "kˈaʊntɪŋ tˈuːl"; sˈiː fˈɪɡjɚ wˌɪtʃ wʌz stˈɪl ɪn jˈuːs ˈæftɚ ðə kˈɑːŋkwɛst ʌv pɚɹˈuː.