Sunan an-Nasa'i, Hadith 2477 ⓘ
It was narrated that 'Ali, may Allah e pleased with him, said: "The Messenger of Allah said: 'I have exempted you from (having to pay Zakah on) horses and slaves. Pay the Zakah on your wealth, for every two hundred (Dirhams), five."'
أَخْبَرَنَا مَحْمُودُ بْنُ غَيْلاَنَ، قَالَ حَدَّثَنَا أَبُو أُسَامَةَ، قَالَ حَدَّثَنَا سُفْيَانُ، عَنْ أَبِي إِسْحَاقَ، عَنْ عَاصِمِ بْنِ ضَمْرَةَ، عَنْ عَلِيٍّ، رضى الله عنه قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " قَدْ عَفَوْتُ عَنِ الْخَيْلِ وَالرَّقِيقِ فَأَدُّوا زَكَاةَ أَمْوَالِكُمْ مِنْ كُلِّ مِائَتَيْنِ خَمْسَةً " .
also referenced under: Book 23, Hadith 0 (In-Book) & Volume 3, Book 23, Hadith 2479 (DarusSalam)