  Event-by-event fluctuations of produced particle multiplicities are believed
to be sensitive to a deconfinement phase transition and the critical point of
strongly interacting matter. The NA49 collaboration has conducted a systematic
study of various fluctuation observables. In this contribution, recent results
on hadron ratio fluctuations in central Pb+Pb collisions at sqrt(s_NN) = 6.3 to
17.3 GeV are reported. These results are complemented by the centrality
dependence of hadron ratio fluctuations at sqrt(s_NN) = 17.3 GeV. A universal
scaling was found, describing the energy and centrality dependence of the (K++
K-)/({\pi}++ {\pi}-) and (p + pbar)/({\pi}++ {\pi}-) ratio fluctuations purely
by a change in the observed average hadron multiplicities. This scaling is
broken for the fluctuations of the (K+ + K-)/(p + pbar) and K+/p ratios,
possibly hinting at a change in the baryon number-strangeness correlation.
