We select Period II (financial crisis)
as the dummy reference category when examining the pattern of influence
of sovereign ratings over time. Interestingly, we find the influence
of sovereign risk to be lower in the sovereign debt crisis periods than in
the financial crisis period. The effect of sovereign ratings on corporate
ratings is also lower in Period I (pre-Lehman Brothers bankruptcy).
This is somewhat in line with our findings on the piercing of the sovereign
ceiling in Table 3