表示上升:

climb, go up, ascend, shoot up，creep up, surge, boom, accrue,leap, soar, jump, increase, rally, rise, rocket, improve,

表示下降:

go down, fall, fall off, drop, slump, decline, decrease, plummet, slide, slip,shrink, dip, reduce, descend, sink, subside, ebb, creep down,

到达顶部:

top out, peak, reach a peak, reach the highest point, peak at..,

触底:

bottom out, hit a trough, reach a low point, reach the rock...

稳定:

level out, even out, remain stable/still/steady, stay constant,keep its stability, remain unchanged...

变化急剧地:

dramatically, drastically, sharply, hugely, enormously, considerably,significantly, markedly, surprisingly, noticeably, substantially...

突然地: abruptly, suddenly

平稳地:

steadily, smoothly, slowly, marginally, gradually, moderately, mildly...

波动:

fluctuate, witness/display/demonstrate a fluctuation,go ups and downs, increase with fluctuation(波动式增长)