These were the worst performers on the ASX 200 last week

Last week, the S&P/ASX 200 Index (ASX: XJO) had its best week in over a year. The benchmark index rose an impressive 3.3% over the five days to finish the period at 7,294.4 points.

Unfortunately, not all shares were able to climb higher with the market. Here's why these were the worst performers on the ASX 200 last week:

Westgold Resources Ltd (ASX: WGX)

The Westgold share price was the worst performer on the ASX 200 last week with a 21.9% decline. The catalyst for this was the successful completion of the gold miner's $100 million institutional placement. Westgold raised the funds at a 13.9% discount of $2.44 per new share. These funds will be used to accelerate the company's Murchison and Bryah growth strategy. This strategy is focused on establishing a systematic pathway towards a +400,000 ounce per annum gold production rate from FY 2024.

Gold Road Resources Ltd (ASX: GOR)

The Gold Road share price was out of form and tumbled 7% last week. Last week the team at Macquarie downgraded this gold miner's shares to an underperform rating with a $1.70 price target. The broker made the move on valuation grounds.

IGO Ltd (ASX: IGO)

The IGO share price wasn't too far behind with a 5.7% decline over the five days. Last week was another wild one for the nickel price, with the battery material crashing to the point that trade was suspended on the LME again. In addition, the company revealed that the proposed acquisition of nickel producer Western Areas Ltd (ASX: WSA) had hit a stumbling block. It said: "Western Areas and the Independent Expert are continuing to consider the implications, if any, on nickel market fundamentals and expectations for medium to long-term nickel prices."

Monadelphous Group Limited (ASX: MND)

The Monadelphous share price was out of form and dropped 4% last week. This was despite there being no news out of the engineering company. However, with its shares up almost 20% in the space of just over a month, some investors may have been taking a bit of profit off the table last week.