Shares of Archer Aviation Inc. ACHR are flat on Thursday. But they have been in a downtrend that may continue.Once significant support breaks, it can create a bearish dynamic. It is why Archer is our Stock of the Day.As you can see on the chart below, the $9.15 level has been important for Archer. It was resistance in March and April. Then it became support in June and August. Price levels that have been resistance converting into support is a common occurrence in the financial markets. It happens because o ...