Effect of the S yield for massive stars on the [S/H] and [S/Fe] radial gradients for the model with a flattened star formation efficiency profile for the outer regions. The solid red line shows the model with standard yield prescriptions (from Kobayashi et al. 2006, 2011), the dashed red line shows the model with the S yield reduced by a factor 4, and the dash-dotted green line displays a model with scaling factor for the S yields that is variable with radius. The symbols are the same as in Fig. 8.