An intriguing observation here – Aries and pisces rising are the least common amongst individuals in the world. In the Northern Hemisphere, Pisces and Aries (which are at the ends of the spectrum) increase for the fastest quantity of time, contrary to the longest, Virgo and Libra, due to the Earths axis. (https://en.wikipedia.org/wiki/Ascendant#Long and short ascension) says that in Paris in France for example, Virgo and Libra rise for 2 hours 45 minutes, whereas Pisces and Aries only 1 hour.
In the Southern Hemisphere its of course the other method round – Aries and pisces rise for the longest time, and Virgo and Libra the least – so more children born as Ari/Pis ascendants. Thinking about that 90% of the worlds population is in the Northern Hemisphere, that in general makes Pisces and Aries the rarest of them all. Likewise when looking deeper in the geography – the most populous nation in the south is Indonesia, which itself is extremely near (and in truth at) the equator – hence the distinctions arent that huge. The most significant populous cities/regions in the south (that are remote enough from the equator) are around the 20-35 ° S latitude mark. In the north meanwhile, many of the biggest places/countries are currently a minimum of 30 ° N: like China, USA, Pakistan, Japan, Egypt, Italy, Turkey, France and so on (and much of these are over 40 ° N, consisting of NY and Chicago). And at 50 ° N and over the likes of England, Germany, Russia etc.
This points that in general worldwide, by rather a shot, Virgo and Libra ascendants are each the most common, whereas Aries and Pisces ascendants are the least.