PR v2.22.3 - Personal Exemptions in Employee Maintenance

Iowa client is asking about personal STATE exemptions.  The IA W4 certificate allows a personal exemption option.  In the IA set up, pers exemptions are greyed out.  The HELP text mentions that this field is available only if the tax group allows personal exemptions.  I reviewed the tax group set up for Iowa and find no field/flag which might activate this field.

Am I looking in the wrong spot, it the help text inaccurate (shocking) or a combination of both.

Thanks in advance