One thing to remember when looking at charts such as that one (there are several versions, some more accurate than others) is that the actual value of a draft pick is whatever the two teams involved decide it is. If one team really wants to trade up or down, it's often willing to overpay or to receive less than what the chart might say is appropriate. Also, more than half of all draft trades are simple two-for-one trades, and only about 10 percent involve more than one pick for each team. So teams don't usually nit-pick over a few "points" here and there, trying to balance out the equation. As long as the values are close and both teams get the picks to suit their purposes, that's usually good enough.
For further reference, here are all of the draft trades since 1996, and almost all of them from 1992-1995 --
1992 DRAFT
4 = 6, 28
17, 120 = 19, 104
19, 37, 104 = 13, 71
20 = 37, 64, 108
36, 121 = 52, 78, 163, 222, 329
40 = 47, 74
47, 74 = 56, 58
56 = 82, 109, 250
1993 DRAFT
11 = 14, 83
13 = 19, 75
18 = 20, 116
20 = 26, 81
29, 112 = 46, 54, 94, 213
33 = 36, 120
41 = 58, 81
41, 82, 110, 138 = 48, next 1st
44 = 49, 107
64 = 82, 104
65 = 73, 127
72 = 81, 152
92 = 100, 156
99 = 110, 138
112 = 119, 156
1994 DRAFT
5 = 7, 83
7 = 15, 56, 100
12 = 13, 144
16 = 20, 89
23, 217 = 28, 62
29 = 40, next 2nd
37 = 40, 118
52 = 55, 125
53 = 84, 149, 175, 190
65 = 89, 115, 121
80 = 94, 152
107 = 121, 135
120 = 126, 169
1995 DRAFT
1 = 5, 36
7, 72 = 12, 43, 63
10 = 30, 94, 119, next 1st
19 = 31, 97, 134, next 4th
22, 188 = 32, 63, 173
28 = 41, 63
29 = 34, 98, 100
33 = 40, 71
41 = 46, 110
51 = next 1st
70 = 82, 115
84 = 90, 160
111 = 121, 196
112 = next 3rd
1996 DRAFT
9 = 17, 48, 109
13 = 18, 83, 201
17 = 21, 91
30 = 37, 67
41 = next 1st
49 = 60, 99
55 = 65, 100, 213
57 = 76, 124, 149
60, 99 = 79, 98, 134, 150
76 = 86, 119, 195
97 = 112, 137
98, next 7th = 113, 125
99 = 110, 146
111 = 122, 159, 235
135 = 161, 162
157 = next 4th
192 = next 5th
1997 DRAFT
1 = 6, 67, 102, 207
3, 63 = 11, 41, 70, 100
6 = 8, 104
6 = 12, 63
13, 110 = 18, 91, 116, 181
22 = 25, 155, next 3rd
38 = 40, 173
54 = 65, 101
55 = 57, 190, 227
67 = 88, 191, 229, next 6th
71 = 84, 188
77 = 86, 156
107 = 116, 165
112 = 121, 170, 173
123 = 157, 166, 203
138 = 215, next 4th
140 = 180, 222
146, 218 = next 3rd
193 = 213
1998 DRAFT
19 = 29, 60
23 = 34, 59
41 = 56, 87, 149
43 = 1st in two years (2000)
45 = 53, 114
59 = 1st in two years (2000)
60 = 79, 143, 172
65 = 67, 195
70 = 85, 116
93 = 103, 124, 154
102 = 112, 142
104 = next 3rd
109 = 113, 191
137 = 199, 203, 215
138 = 162, 197
152 = 156, next 6th
200 = next 6th
215 = next 6th
1999 DRAFT
5 = 12, 71, 107, 144, 179, 218, next 1st, next 3rd
7 = 12, 71, 106, 143, next 3rd
17 = 20, 82, 191
20 = 22, 140
24 = 27, 134
27 = 39, 70, 142
37 = 40, 144
40, 102 = 47, 78, 111
42 = next 1st
43 = 54, 84, next 6th
44 = 59, 73, 163
46 = 52, 117
70 = 72, 232
96 = 99, 171
137 = next 4th
146, 163 = next 3rd
165 = 179, 218
170 = 187, 191
174 = 184, 207
182 = 195, 233
207 = 221, 253
2000 DRAFT
3 = 12, 24, 119, 154
10 = 15, 45
12 = 16, 48
51 = 57, 120
61 = 68, 135
86 = 119, 154
98 = 108, 132
111 = next 3rd
104 = 125, 150, 225
138 = 158, 195
150 = 170, 209
154 = 175, 231
209, 225 = 223, 232, 254
212 = next 6th
231 = next 6th
238 = next 6th
2001 DRAFT
7, 191 = 9, 82, 222
14 = 21, 51
22 = 30, 91, 193
37 = 52, 81
39 = 50, 112
48 = 50, 173
51 = 58, 110
52 = 56, 122
53 = 70, 81
61 = 78, 114
69 = 86, 119
88, 187 = next 2nd
96 = 112, 139
145 = 154, 186
149 = 180, 216
170 = next 5th
215, 219, 226 = next 4th
2002 DRAFT
6 = 8, 75, next 6th
14 = 15, 110
18 = 21, 89
17 = 18, 158
20, 156 = 28, 60
21 = 32, 96, 234
52, 96 = 56, 87
61 = 69, 102
63, 129 = 72, 104, 140
67 = 73, 145
79 = 89, 118
96 = 112, 155
116 = next 3rd
117 = 131, 144
122 = 147, 189
168 = 237, next 5th
2003 DRAFT
4 = 13, 22, 116
6, 37, 102 = 17, 18, 54
13 = 14, 193
15 = 30, 62
16 = 27, 92, 200
19 = 41, next 1st
36, 117 = 41, 75
45 = 50, 120
78 = next 2nd
79 = 94, 127
82 = 108, 120, 227
83, 262 = next 2nd
120 = 128, 157
138 = next 4th
143 = 176, 193, 218
147 = 165, 203
150, 200 = 153, 189
154, 225 = 164, 201, 243
166 = 185, 244
181 = 226, 247
245 = next 6th
2004 DRAFT
1 = 4, 65, next 1st, next 5th
6 = 7, 37
16 = 28, 58
19 = 20, 119
22 = 43, 144, next 1st
24 = 26, 123
27, 159 = 40, 71, 103, 138
28 = 31, 127
29, 90 = 38, 69, 125
30 = 36, 105, next5th
38 = 44, 107
48 = 50, 151
55 = 70, 102
59, 161 = 68, 141, 173
72 = 86, 118
81, 151 = 139, next 2nd
82 = 88, 155
87 = 102, 153
104 = 112, 147
153 = 160, 222
156 = 182, 206
159 = 175, 210
174 = 186, 219
179 = 188, 226
182 = 205, 223
Looking at only the two-for-one trades also gives you a good idea of what picks can be had or are needed for trading from one spot to another --
1 = 5, 36
4 = 6, 28
5 = 7, 83
6 = 7, 37
6 = 8, 104
6 = 12, 63
10 = 15, 45
11 = 14, 83
12 = 13, 144
12 = 16, 48
13 = 14, 193
13 = 19, 75
14 = 15, 110
14 = 21, 51
15 = 30, 62
16 = 20, 89
16 = 28, 58
17 = 18, 158
17 = 21, 91
18 = 20, 116
18 = 21, 89
19 = 20, 119
19 = 29, 60
20 = 22, 140
20 = 26, 81
23 = 34, 59
24 = 26, 123
24 = 27, 134
28 = 31, 127
28 = 41, 63
30 = 37, 67
33 = 36, 120
33 = 40, 71
37 = 40, 118
37 = 40, 144
37 = 52, 81
38 = 40, 173
38 = 44, 107
39 = 50, 112
40 = 47, 74
41 = 46, 110
41 = 58, 81
44 = 49, 107
45 = 50, 120
45 = 53, 114
46 = 52, 117
48 = 50, 151
48 = 50, 173
49 = 60, 99
51 = 57, 120
51 = 58, 110
52 = 55, 125
52 = 56, 122
53 = 70, 81
54 = 65, 101
55 = 70, 102
61 = 68, 135
61 = 69, 102
61 = 78, 114
64 = 82, 104
65 = 67, 195
65 = 73, 127
67 = 73, 145
69 = 86, 119
70 = 72, 232
70 = 82, 115
70 = 85, 116
71 = 84, 188
72 = 81, 152
72 = 86, 118
77 = 86, 156
79 = 89, 118
79 = 94, 127
80 = 94, 152
82 = 88, 155
84 = 90, 160
86 = 119, 154
87 = 102, 153
92 = 100, 156
96 = 99, 171
96 = 112, 139
96 = 112, 155
97 = 112, 137
98 = 108, 132
99 = 110, 138
99 = 110, 146
102 = 112, 142
104 = 112, 147
107 = 116, 165
107 = 121, 135
109 = 113, 191
111 = 121, 196
112 = 119, 156
117 = 131, 144
120 = 126, 169
120 = 128, 157
122 = 147, 189
135 = 161, 162
138 = 158, 195
138 = 162, 197
140 = 180, 222
145 = 154, 186
147 = 165, 203
149 = 180, 216
150 = 170, 209
153 = 160, 222
154 = 175, 231
156 = 182, 206
159 = 175, 210
165 = 179, 218
166 = 185, 244
170 = 187, 191
174 = 184, 207
174 = 186, 219
179 = 188, 226
181 = 226, 247
182 = 195, 233
182 = 205, 223
207 = 221, 253