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We use recently digitized sunspot drawings from Mount Wilson Observatory toinvestigate the latitudinal dependence of tilt angles of active regions and itschange with solar cycle. The drawings cover the period from 1917 to present andcontain information about polarity and strength of magnetic field in sunspots.We identify clusters of sunspots of same polarity, and used these clusters toform ``bipole pairs''. The orientation of these bipole pairs was used tomeasure their tilts. We find that the latitudinal profile of tilts does notmonotonically increase with latitude as most previous studies assumed, butinstead, it shows a clear maximum at about 25--30 degree latitudes. Functionaldependence of tilt ($\gamma$) on latitude ($\varphi$) was found to be $\gamma =(0.20\pm 0.08) \sin (2.80 \varphi) + (-0.00\pm 0.06)$. We also find thatlatitudinal dependence of tilts varies from one solar cycle to another, butlarger tilts do not seem to result in stronger solar cycles. Finally, we findthe presence of a systematic offset in tilt of active regions (non-zero tiltsat the equator), with odd cycles exhibiting negative offset and even cyclesshowing the positive offset.

Tilt of sunspot bipoles in Solar Cycles 15 to 24