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I think we don't have enough depth of data on even the best-known exoplanetary systems to really answer your question the way you mean it, but there are some things we do know, and some interesting comparisons and generalizations we can make because of that.

First off, a little cursory review of the data says it's actually 99.86% for our system, or only 14 parts out of 10,000 of the mass in the planets, not 2%. Of that 0.14%, around 70% is in Jupiter (and 20% in Saturn, and around 3-4% each in Neptune and Uranus).

That means ~98-99% of the mass outside the Sun is in the gas giants. THAT makes your question much more complicated, but also much more interesting!

The amount and composition of mass outside of the parent star, in a planetary system, is probably controlled mostly by what the protoplanetary nebula which the star and planets accreted/condensed from was like, very broadly. How dense the gas and dust was, what it was made of, how fast it was moving relative to other gas and dust and neighboring stars' stellar wind, the influence of shockwaves from supernovae, and so on. If you make cloud of matter dense enough, it makes new stellar systems, and what they come out like depends on what the cloud had in it and exactly how everything was arranged when it got nudged.

With that in mind, we can guess a lot about this from the star(s) that result by looking at the spectra of their light. Stars with more elements past Helium have a higher 'metallicity' (formal astrophysics term), which we can just measure from the gaps in the light wavelengths from the star. If there's more oxygen, nitrogen, carbon, silicon, iron, and heavier elements in a given stellar system, it's likely that it has more planets, period, but also more rocky planets.

Back to that 98% of the mass being in gas giants...well, if that's normal for a star the size, age, and metallicity of our Sun, there are a LOT of astronomical scenarios where metal-poor stars could have many gas planets, or a high-metallicity star could have had local orbital dynamics (in a binary/trinary stellar system) that meant no large planets could form at all, and ~100% of the mass in the system is in the star (or stars), or doing its own thing in some other object's gravitational influence after being flung away billions of years ago.

One important thing we don't know is how many planets are too small, too highly inclined in their orbits, too distant from their star, or otherwise undetectable by current methods in any given extraplanetary system. The thing is, if we're talking about 0.14% of the mass of the system, it could vary hugely and we wouldn't know from the effect on the parent stars. The wobble from Hot Jupiters face-hugging their parent red dwarf stars is teeny tiny. There might be planetary systems facing us flat-on with their ecliptic planes, too, among other things.

So, I guess that's a long way of saying 'it appears other planetary systems are similar to ours, but we have no way of knowing if that's because it's true, or because it just looks that way from the available data.'

All of that said, we're collecting an incredible quantity and quality of new data now, so a lot of this will be less...entirely based on physics simulations and extrapolating from what we can observe locally.

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We do not have data for the lower end, but we do have some clue of where the higher end may be. We already have discovered a few systems where the mass fraction is very different from the Solar System’s (where planets take up ~0.134% of all system mass). Going by Wiki numbers, Gliese 876’s mass fraction within known planets is almost 1%, while Titawin and HR 8799 both have that number at almost 2%.

There's one big caveat to add on to this as well: a lot of current conjecture is that more stars are in multi-star systems than not. //Don't have a reputable source for this, am armchair at best with any of this.

I don't know how widely accepted it is that more stars are in binaries+ than not; regardless, in those systems you'd have a large variation in planetary creation and a non-trivial percentage mass in the partner star.

Oh, yeah, it's actually pretty widely agreed that most stars are in multiple systems, although I have no idea how many of those are on the scale of thousands or more AUs. Close-in binaries and trinaries churn everything up in such a way as to ensure planet formation doesn't really happen, according to lots of simulations and some pretty solid first principles physics justifying all of that.

It also depends on what you call a star and a planet. Consider a young Brown dwarf of 13.2 Jupiter masses that fuses deuterium with Super Jupiter of 12.9 Jupiter masses. Is that a star system with almost 50% of its weight outside the star or is it a binary rogue planet system or is it neither?