Regardless of the market's daily gyrations, the downtrend over the last year is enough to rattle many investors. It can get pretty discouraging to see your portfolio falling week after week, and it's even harder to see this happen without knowing for how long the market can fall. 

Nonetheless, right now's the time when the fortunes of 2030 are being made. With the right investments in businesses that have long-term appreciation potential, you could at least feel a bit better about what's happening in the present.

There are a couple of stocks that are particularly alluring right now, so let's dive into a discussion of each.

1. Steris

Steris (STE -0.55%) makes the sterilization products that your doctor's office uses to keep its clinical areas safe, clean, and ready for patients, which is what makes it a prime candidate for a long-term investment.

Indeed, 80% of its revenue, which totaled more than $3.1 billion in 2021, is from recurring sales of things that healthcare companies will always need more of, like antiseptic wipes and disinfectants. The rest is from sales of its capital equipment, which includes products like autoclaves that are designed for customers to use to sterilize their tools and to render biohazard waste safely disposable.

Furthermore, because hospitals need to sterilize practically everything, the more people who utilize healthcare and the more procedures that hospitals perform, the more demand there will be for Steris' goods and services. That means population growth is a driver of future returns, as is the advancement of medical technologies that enable more conditions to be treated.

Importantly, healthcare systems need Steris' offerings regardless of how dire economic conditions are, as they can't provide their services to patients otherwise. So when management estimates that the company's total revenue will grow at between 5% and 9% every year for the long term, it's a pretty safe bet that they're right.

And over the years, that'll add up into tidy returns for shareholders, especially thanks to the stock's dividend. It grew 147% over the last 10 years and currently has a forward yield of around 1.1%.

2. Costco

Costco Wholesale (COST 0.69%) is another growth stock that could be a source of portfolio optimism during this bear market if you invest. The company's network of 838 warehouses are favorites among consumers as they're where you can find cheap but decent-quality goods sold in bulk. Costco charges a membership fee of $60 per year for the privilege of shopping at its locations, and 92.6% of its members renew every year, so it has a customer base that's quite loyal on average.

Part of its pitch to investors is that it's always going to be selling the groceries, gasoline, clothing, medicines, and practically everything else that consumers are going to need, and it can always pad its profit margin by hiking the membership fee. In its 2021 fiscal year, Costco brought in more than $192 billion in sales, making it among the largest companies in the world.

What's more, despite its razor-thin profit margin, it has a long history of growing its earnings year after year. In the last 10 years, its trailing-12-month net income rose by 224%, and thanks to constantly adding new product and service offerings, it should be able to do roughly the same in the next 10 years without changing anything significant about its business model.

With such steady earnings growth, it's no surprise the company opts to pay a dividend, which it hikes frequently. While its forward yield of around only 0.7% won't make investors rich quickly, Costco occasionally pays special dividends when it has extra cash, such as most recently in late 2020.

Even if its shares dip during this bear market, this business isn't going anywhere, and in the long run, its ongoing expansion into Canada and other international locales only furthers its prospects -- making this a good growth stock to bet on today.