diff --git a/src/updater/csv_source.cpp b/src/updater/csv_source.cpp
index 0f6f12237..fe13a7477 100644
--- a/src/updater/csv_source.cpp
+++ b/src/updater/csv_source.cpp
@@ -34,10 +34,11 @@ namespace csv
 SegmentLookupTable readSegmentValues(const std::vector<std::string> &paths)
 {
     static const auto value_if_blank = std::numeric_limits<double>::quiet_NaN();
+    const qi::real_parser<double, qi::ureal_policies<double>> unsigned_double;
     CSVFilesParser<Segment, SpeedSource> parser(
         1,
         qi::ulong_long >> ',' >> qi::ulong_long,
-        qi::double_ >> -(',' >> (qi::double_ | qi::attr(value_if_blank))));
+        unsigned_double >> -(',' >> (qi::double_ | qi::attr(value_if_blank))));
 
     // Check consistency of keys in the result lookup table
     auto result = parser(paths);