The number is from the unions and organizers involved in the strike. The sum of their members lists I would guess. « The huge mobilisation, which organisers sa

The number is from the unions and organizers involved in the strike. The sum of their members lists I would guess. « The huge mobilisation, which organisers said involved 250 million people » https://www.wsws.org/en/articles/2020/11/27/indi-n27.html https://www.wsws.org/en/articles/2020/11/27/indi-n27.html