What industry does the wealth bank in the ancient thirty-six lines refer to?

Farming once, studying twice, three dozen irons, four or five sailboats in grinding bean curd,

Six Woods, seven bamboos, eight carved flowers, nine spinning and ten weaving lang,

1 1 tailors make clothes, 12 are tinkers,

Thirteen grocers, fourteen polishers,

Fifteen shoemakers' shoes, sixteen sawworkers suffer,

Seventeen monks play outfield, eighteen nuns play and sing,

Nineteen Taoist priests sang the phoenix, and twenty boys counted the land halls.

Twenty-one Jingling fortune tellers, twenty-two face-to-face readers,

Twenty-three hexagrams wear robes, and twenty-four fishing drums sing love.

The woodcutter is on the mountain; 26 doctors sell fake drugs,

Twenty-seven fun tricks to sing, twenty-eight fists to keep fit,

Twenty-nine martial arts performers went out to repair umbrellas on thirty rainy days.

Thirty-two people go out to sharpen scissors on sunny days, and thirty-two people repair the house the dirtiest.

Thirty-three pick eight, thirty-four three-person sedan chairs,

Thirty-five is a barber, and the last line is to see the cowherd.

Up and down 30 lines, each line always has a champion,

If you ask which cow? It's Emperor Zhu Hongwu.

I guess it may be a singer!