System.FormatException: Input string was not in a correct format.
   at System.Number.ParseSingle(String value, NumberStyles options, NumberFormatInfo numfmt)
   at System.Single.Parse(String s)
   at ASP._Page_Views_MacroPartials_theme_AirInfo_cshtml.Execute() in C:\gip\umbraco_ap\Views\MacroPartials\theme\AirInfo.cshtml:line 197
   at System.Web.WebPages.WebPageBase.ExecutePageHierarchy()
   at System.Web.Mvc.WebViewPage.ExecutePageHierarchy()
   at System.Web.WebPages.WebPageBase.ExecutePageHierarchy(WebPageContext pageContext, TextWriter writer, WebPageRenderingBase startPage)
   at Umbraco.Core.Profiling.ProfilingView.Render(ViewContext viewContext, TextWriter writer)
   at Umbraco.Web.Mvc.ControllerExtensions.RenderViewResultAsString(ControllerBase controller, ViewResultBase viewResult)
   at Umbraco.Web.Macros.PartialViewMacroEngine.Execute(MacroModel macro, IPublishedContent content)
   at umbraco.macro.LoadPartialViewMacro(MacroModel macro)
   at umbraco.macro.renderMacro(Hashtable pageElements, Int32 pageId)
   at Umbraco.Web.UmbracoComponentRenderer.RenderMacro(macro m, IDictionary`2 parameters, page umbracoPage)
   at ASP._Page_Views_Partials_TypedGrid_Editors_macro_cshtml.Execute() in C:\gip\umbraco_ap\Views\Partials\TypedGrid\Editors\macro.cshtml:line 16
   at System.Web.WebPages.WebPageBase.ExecutePageHierarchy()
   at System.Web.Mvc.WebViewPage.ExecutePageHierarchy()
   at System.Web.WebPages.WebPageBase.ExecutePageHierarchy(WebPageContext pageContext, TextWriter writer, WebPageRenderingBase startPage)
   at Umbraco.Core.Profiling.ProfilingView.Render(ViewContext viewContext, TextWriter writer)
   at System.Web.Mvc.Html.PartialExtensions.Partial(HtmlHelper htmlHelper, String partialViewName, Object model, ViewDataDictionary viewData)
   at ASP._Page_Views_Partials_TypedGrid_Editors_Base_cshtml.Execute() in C:\gip\umbraco_ap\Views\Partials\TypedGrid\Editors\Base.cshtml:line 18