AbstractLet c be a nonzero constant and n a positive integer, let f be a transcendental meromorphic function of finite order, and let R be a nonconstant rational function. Under some conditions, we study the relationships between the exponent of convergence of zero points of $f-R$
f
−
R
, its shift $f(z+nc)$
f
(
z
+
n
c
)
and the differences $\Delta _{c}^{n} f$
Δ
c
n
f
.