Why would the onChange event of InputText not fire in Blazor?

I have the following razor markup in a blazor component:

<div class="form-group row"><label for="name">Contact: </label><InputText id="name" @bind-Value="Contact.Name" @onchange="NameChanged"></InputText></div>

When I modify the contact name on the form and tab out of the control the NameChange method is never called. Is there something else that I need to do in order to get the onChange event to trigger?