Cryptomarket is unpredictable and high fluctuate so ethereum price is going up or down although last two years there is no good improvement In Ethereum price because for long term it's price going under $200 but this ethereum will be jump in bull run because ethereum 2.0 will be released and BTC halving finished.
I do not think that in the long run the price of ethereum will be below $ 200. This coin is able to grow much in price, especially after the full implementation of the Ethereum 2.0 improvements, which are already at the testing and error correction stage.
As for the stability in the price of ethereum, it is unlikely that this coin can ever be stable in its price. A decentralized cryptocurrency cannot have a more or less stable price, since their price is formed solely on the basis of supply and demand, which can never even be relatively stable.