The level of information security of private companies using Estonia's X-Road® secure national data exchange is not adequately checked when joining and using the system, the National Audit Office (Riigikontroll) finds, though the system as a whole is reliable, the office says, and updating the stated government requirements on X-Road could fix the issue. The volume of inquiries made via X-Road – on average, 133 million per month – means the provision of the majority of public services would be rendered either impossible or significantly more difficult should the exchange not be operational, the audit office also found. Replacing data exchange carried out via X-Road (Estonian: X-Tee) with non-electronic data exchange would be practically impossible or at least very costly, the office adds.