Amid demands by parties to increase the number of polling stations where VVPAT slips are matched with EVM results, Chief Election Commissioner Sunil Arora on Sunday said the poll panel will take a final call on the issue after the Indian Statistical Institute submits a report on it. As of now, voter-verifiable paper audit trail (VVPAT) machines are used in all polling stations but results of EVMs and VVPATs are matched in one polling station per constituency. VVPAT or paper trail machine is a device which dispenses a slip with the symbol of the party for which a person has voted for. The slip appears on a small window for seven seconds and then drops in a box. The voter cannot take it home. There have been demands to increase the number of polling stations where EVM and VVPAT results are matched to dispel fears about electronic voting machines being 'hacked' to favour a particular political party. Parties parties have demanded that 10 to 30 per cent paper trail slips per constituency be counted to ensure there is no rigging and to assure voters that the electronic voting machines are working fine and have not been rigged. The EC has been brainstorming over increasing percentage of VVPAT slips since 2016. Then CEC Nasim Zaidi had pushed for an early decision but little progress was made. Arora said the Indian Statistical Institute's report is expected before counting process and the EC will then take a call on the issue.