Coca-Cola's Q2 unit case volume growth, a key indicator of sales volume, was flat. This suggests that there was no significant change in the company's sales volume during the quarter. This could potentially impact the company's stock price, as investors may interpret this as a sign of stagnation in the company's growth. However, the impact may not be significant as the flat growth was due to offsetting factors - growth in some markets was offset by declines in others.