Return Impact !!! Bond Convexity Spread (-Sign) why, change, positive, increase, problem

liquidity

The formula says:
Return impact = modified duration * change in spread.
In a schweser problem, the spread narrows and it’s shown as a negative sign???  why is this the case?
If the spread had widen, would this be a +positive sign for the spread change?
My reasoning: if the spread narrows, the return impact will be an increase in bond price due to a lower denominator.

segalm

An 8-year semiannual-pay corporate bond with a 5.75% coupon is priced at $ 1 0 8.32.
This bond’s duration and reported convexity are 6.4 and 0.5. The bond’s credit spread
narrows by 75 basis points due to a credit rating upgrade. Estimate the return impact
with and without the convexity adjustment.

ishfaque

Is this the whole question? I am assuming when they say duration, they mean modified duration. Since the spread narrows, the spread adjustment is negative.
Return Impact = -(Duration x Spread) + 0.5 x Convexity x Spread^2 = -(6.4 x -0.0075) + 0.5 x 50.0 x -0.0075^2 = 0.0494 or +4.94%.
Spread narrows  interest rates decrease  price goes up.
What is Schweser’s explanation for the answer?