How to Bind TextBox from Multiple Other Controls

Question

What I Have

I have a form with 3 UserControls that contain source fields to be used to calculate another field in a target UserControl.

UserControl1 (uc1)

• StartDate DatePicker (dpStart)
• EndDate DatePicker (dpEnd)

UserControl2 (uc2)

• Rate TextBox (txtRate)

UserControl3 (uc3)

• Amount TextBox (txtAmount)

UserControl 4 (uc4)

• CalculatedValue TextBox (txtCalc)

Formula to calculate txtCalc is below

txtCalc.Text = (dpEnd.Value - dpStart.Value).TotalDays * txtRate.Text * txtAmount.Text

What I Want To Achieve

Whenever I change a value in any of the first 3 UserControls, the Text in txtCalc should update with calculated value.

What I Have Tried

I have tried DataBindings but it appears to be only for a single field.

e.g.

uc4.txtAmount.DataBindings.Add("Text", uc2.txtRate, "Text", true, DataSourceUpdateMode.Never);

Would really appreciate your inputs.