In general, storage capacity depends on which image size and quality you have selected.
For your information, here is the number of images recordable in a 16MB SD Memory Card in the respective image size and quality. Since the image size may vary depending on scenes and subjects, these are approximate values only.
Economy: 29/56/82/226
Standard:14/29/45/150
Fine: 7/15/23/82
Super Fine: 1/2/3/15
(Pixel Size: 2272x1704/1600x1200/1280x960/640x480)
Movie: 41 sec.
Audio Recording: 30 min. 9 sec.