Uttar Pradesh traders have asked the state government to allow quarterly filing of returns with the trade tax department instead of the present monthly filing. They said the monthly system not only burdened them with added paper and administrative work but also bred corruption at the lower echelons of the department. “The tax department should also abolish a separate VAT audit and check harassment of traders by mobile checking units,” UP Adarsh Vyapar Mandal President Sanjay Gupta said.