Understanding Bond Yields According to Bloomberg, the coupon rate on a 10-year UK government bond is 4.75%.

Bloomberg also states that the yield is currently 0.55%, and the market price £143.51.

But if the following formula is correct:



Then the yield should be $\frac{4.75}{143.51} \approx 3.31$%

Clearly this isn't the case. So what did I do wrong?
You did not apply your formula correctly.

Your top formula is correct. But in your bottom formula, the numerator on the left side of the equation is a percentage. It should, instead, be a monetary unit of £ in this case.

The annual coupon payment should be denominated in £. Not a percentage. Otherwise, the units don't balance each other and don't match the units of the original equation.

Edit:

I noticed in your comment you include some information that was left out of the original question: that the par value is £100.

That's why I asked for a link to the source of the Bloomberg report. These numbers would make more since if the par value were £1,000