Swimming Efficiency not available?

I am working on a swimming datafield and wanted to include Swimming efficiency
The manual has this:
[HTML] var swimEfficency; // Swim efficence[/HTML]

But this line throws an error:
fieldValue= (info.swimEfficency != null) ? info.swimEfficency : 0;
While an almost indentical line doesn't:
fieldValue= (info.swimStrokeType != null) ? info.swimStrokeType : 0;

The error is: "Undefined symbol "swimEfficency" detected."

It could be a typo, as the manual says Efficency and efficence while I gues it should be Efficiency (Dutch native speaking, so I could be wrong).
But with info.swimEfficiency also no joy.

Am I missing something?