"Tax indicator for material" update

Hi experts,

I have to read and update the field "Tax indicator for material" (MG03STEUMM-TAXIM) in the purchasing view of a material. (see enclosed picture)

I'd like to avoid to update it with a call transaction, I'd rather update it with a bapi (or a function module).

I found the bapi BAPI_MATERIAL_SAVEDATA, which is very interesting and allows to update nearly all fields of a material master... but not the Tax indicator for material....

Do you know any bapi allowing to update this field, or do you have any other idea on how to proceed ?

Thanks for your help !

Philippe