Dioceses of the Syriac Orthodox Church
In the period of its greatest expansion, in the tenth century, the Syriac Orthodox Church had around 20 metropolitan dioceses and a little over a hundred suffragan dioceses. By the seventeenth century, only 20 dioceses remained, reduced in the twentieth century to 10.
Source: Wikipedia — Dioceses of the Syriac Orthodox Church (CC BY-SA 4.0)