Concatenate 2 columns

Please see attached xls file.

We need to concatenate Columns E (Route) and F (Segment Number) into Column M (ROUTESEG)

As you will see in Column L (RouteSegxxx) the tenth decimal place (.0) does not carry over into the solution.

Column M (ROUTESEG) needs to be to the tenth place (.0)
i.e. 100-101.0
100-102.0
100-103.0
etc.

using =CONCATENATE(E2,"-",F2) does not result in (.0)s

Any help with this would be greatly appreciated!

this tenth place (.0) designation is a requirement when doing "Join" functions in ArcGIS software.