New Delhi, Oct 24: Opposition parties on Tuesday said they would observe November 8 as Black Day to protest against the "ill-conceived" decision of the government to spike Rs 500 and Rs 1,000 currency notes, a year ago. Leader of the Opposition in the Rajya Sabha Ghulam Nabi Azad told reporters that the opposition parties have worked out a joint strategy and would register their protest against the November 8, 2016, demonetisation decision. "Demonetisation was an ill-conceived and hasty decision of the government. It is unprecedented, perhaps in the entire world, that a government had to alter its policy 135 times within a month," Azad said, recalling how the government kept changing its rules in the aftermath of the note ban last year. The decision to mark November 8 as the black day was taken at a coordination meeting on Monday that was attended by JD-U rebel leader Sharad Yadav, CPI MP D. Raja, DMK MP Kanimozhi, BSP's Satish Mishra and Trinamool Congress' Derek O'Brien.