In its annual report for 2016-17, the RBI said that out of 632.6 crore pieces of Rs 1,000 currency notes in circulation, 8.9 crore have not been returned post the note ban last November.
The government had on November 8, banned old Rs 500 and Rs 1,000 notes in an attempt to weed out black money in the country. The old notes were allowed to be deposited in banks, with unusual deposits coming under income tax scrutiny.
The government replaced old Rs 500 notes with new ones, but no replacement for Rs 1000 notes has been made. Instead, a new Rs 2,000 note was introduced post note ban.
RBI said there were as many 588.2 crore of Rs 500 notes, both old and new in circulation as of March 31, 2017. As of March 31, 2016, there were 1,570.7 crore Rs 500 notes in circulation.
The report further said that the cost of printing of currency notes more than doubled to Rs 7,965 crore in 2016-17 from Rs 3,421 crore in the previous year on account of new currency printing.
Besides, new Rs 500 and Rs 2000 notes, the RBI has also printed new Rs 200 notes.