It was a good 12 months for Aussie investors during FY 2025 with the S&P/ASX 200 Index (ASX: XJO) recording a gain of 10.2%.
Unfortunately, not all shares climbed with the benchmark index.
For example, the ASX 200 shares listed below were the worst performers on the index with very disappointing declines. Here's what happened:
IDP Education Ltd (ASX: IEL)
The IDP Education share price was the worst performer on the ASX 200 index with a decline of 75%. Investors were selling the language testing and student placement company's shares following a particularly poor performance in FY 2025. For example, a market update in May revealed that its key destination markets continue to be impacted by policy uncertainty. As a result, IDP Education is expecting to report a 28% to 30% drop in student placement volumes and an 18% to 20% decline in language testing volumes for FY 2025. This is expected to lead to its EBIT almost halving year on year.
Mineral Resources Ltd (ASX: MIN)
The Mineral Resources share price was out of form and dropped 61% over the 12 months. This mining and mining services company's shares came under pressure due to weak iron ore and lithium prices. In addition, the company's precarious balance sheet has many believing that a capital raising will be required in the near future.
Pilbara Minerals Ltd (ASX: PLS)
The Pilbara Minerals share price wasn't far behind with a decline of 57% during the financial year. This lithium miner's shares were sold off after lithium prices crashed on oversupply concerns. This meant that Pilbara Minerals went from recently printing money and paying a dividend to posting a loss and conserving as much cash as it could. This includes deferring its Midstream Project plans.
Polynovo Ltd (ASX: PNV)
The Polynovo share price sank 49% over the 12 months. This medical device company's shares were under pressure after its sales growth came in softer than expected. Concerns over the impact of US trade tariffs may also have weighed on sentiment.
Nufarm Ltd (ASX: NUF)
The Nufarm share price lost 47% of its value during FY 2025. This crop protection company's shares were sold off following the release of its half year results. Nufarm posted a 3% lift in revenue to $1,811 million but a 39% decline in statutory net profit after tax to $29.8 million. The main drag was its Seed Technologies business, which reported revenue of $249 million and a 71% decline in underlying EBIT to $15.9 million. This reflects lower licensing revenues, lower margins in omega-3, and lower canola revenues in Australia.