Why Tax Rates from US are NOT shown in Queries via sdk?

Hi experts,

I am looking forward to update tax rates by PDI.

With a code like the following, I only retrieve ONE record. This is incorrect, since in US I have a tax rate per state.

var item = this.Item.GetFirst();
var query= TaxRate.QueryByElements;
var resultData =query.ExecuteDataOnly();//2.Selection
var selectionParams =query.CreateSelectionParams();
selectionParams.Add(query.CountryCode,"I", "EQ", "US");//Result
 resultData =query.ExecuteDataOnly(selectionParams);

I see only one record in SDK (also if I debug the code)

When I see multiple rates for US in SAP ByD:

Am I looking for in the wrong Business Object?

Thanks in advance,