21.over the period from...to...the...remained level.
在……至……期间,……基本不变。
22.in the year between...and...
在……年到……期间……
23.in the 3 years spanning from 1995 through 1998...
1995年至1998三年里……
24.from then on/from this time onwards...
从那时起……
25.the number of...remained steady/stable from (month/year) to (month/year).
……月(年)至……月(年)...的数量基本不变。
26.the number sharply went up to...
数字急剧上升至……
27.the percentage of...stayed the same between...and...
……至……期间的比率维持不变。
28.the figures peaked at...in(month/year)
……的数目在……月(年)达到顶点,为……
29.the percentage remained steady at...
比率维持在……
30.the percentage of...is slightly larger/smaller than that of...
……的比例比……的比例略高(低)。