I want to generate a new variable showing total hours of care per month.
I generate this variable based on the following three variables: hours, minutes and days (frequency per month).

1) total minutes per care day
2) total minutes per month
3) total hours per month

1) generate padlhrsrevis=(rudpadlhrs_*60+rudpadlmin_)

2) gen padltotmin=(rudpadlhrs_*60+rudpadlmin_)*rudpadlday s_

3) gen padlhrsmonth= padltotmin/60

*Note: Abbreviations: RUD - Resource utilization dementia, PADL - personal actvivities of daily living
Not suprisingly, I see that multiplying/dividing with missing values within the row hours minutes days creates missing values in variable 3) total hours of care per month.
See an excerpt (N=200) om my data below, and see specifically row 191 for an example. If I got missing hours, and the values 30 minutes and 4 days - it will show missing in variable 3) total hours of care per month. However, if hours is 0, this would still generate the correct value 2 hours per month.
Thus, I'm kindly asking if anyone have suggestions on how I can solve this, though - my approach is probably not the most sophisticated one

Code:
* Example generated by -dataex-. For more info, type help dataex
clear
input float(id_real rudpadlhrs_new) byte rudpadlmin_ int rudpadldays_ float(padlhrsrevis_new padltotmin_new padlhrsmonth_new)
  1   0  0  0   0    0         0
  2   .  . 30   .    .         .
  3   0 20  7  20  140 2.3333333
  4   1  0  7  60  420         7
  5   0  0  0   0    0         0
  6   .  .  .   .    .         .
  7   2  0 30 120 3600        60
  8   .  .  .   .    .         .
  9   1 30 12  90 1080        18
 10   0  0  0   0    0         0
 11   .  . 15   .    .         .
 12   0  0  0   0    0         0
 13   0  0  0   0    0         0
 14   0 10  8  10   80 1.3333334
 15   0  0  1   0    0         0
 16   0  0  0   0    0         0
 17   0  0 30   0    0         0
 18   .  . 30   .    .         .
 19   0  0  8   0    0         0
 20   2 30 12 150 1800        30
 21   0  0  8   0    0         0
 22   .  . 30   .    .         .
 23   .  . 31   .    .         .
 24   0  0  0   0    0         0
 25   .  .  0   .    .         .
 26   1  0 30  60 1800        30
 27   .  .  0   .    .         .
 28   .  . 12   .    .         .
 29   0  0  0   0    0         0
 30   .  . 15   .    .         .
 31   3  0 30 180 5400        90
 32 4.5  0 30 270 8100       135
 34   .  .  0   .    .         .
 35   0  0  0   0    0         0
 36   0  0  0   0    0         0
 37   0  0  0   0    0         0
 38   .  .  9   .    .         .
 39   .  . 30   .    .         .
 40   .  . 30   .    .         .
 41   .  .  0   .    .         .
 42   .  .  3   .    .         .
 43   0  0  0   0    0         0
 44   1 30 30  90 2700        45
 45   0  0  0   0    0         0
 46   0  0  0   0    0         0
 47   .  .  .   .    .         .
 48   0  0  7   0    0         0
 49   0 20 20  20  400  6.666667
 50   0  0  0   0    0         0
 51   0  0  0   0    0         0
 52   0  0  0   0    0         0
 53   0  0  0   0    0         0
 54   0  0  0   0    0         0
 55   0  0  0   0    0         0
 56   0  0 30   0    0         0
 57   0  0  0   0    0         0
 58   0  0  0   0    0         0
 59   .  . 30   .    .         .
 60   0  0  0   0    0         0
 61   0 30 20  30  600        10
 62   .  . 30   .    .         .
 63   4 30 30 270 8100       135
 64   0  0  0   0    0         0
 65   0  0  0   0    0         0
 66   0  0  0   0    0         0
 67   0 45 30  45 1350      22.5
 68   2  0 30 120 3600        60
 69   0  0  0   0    0         0
 70   2  0  7 120  840        14
 71   0  0  0   0    0         0
 72   2  0  7 120  840        14
 73   0  0  0   0    0         0
 74   0  0  0   0    0         0
 75   0  0  0   0    0         0
 76   0  0  0   0    0         0
 77   .  .  0   .    .         .
 78   1 30 30  90 2700        45
 79   2 30 12 150 1800        30
 80   0  0  0   0    0         0
 81   0  0  0   0    0         0
 82   .  .  8   .    .         .
 83   0  0  0   0    0         0
 84   0  0  0   0    0         0
 85   .  . 30   .    .         .
 86   0  0  0   0    0         0
 87   0  0  0   0    0         0
 88   0  5  8   5   40  .6666667
 89   0  0  0   0    0         0
 90   .  .  .   .    .         .
 91   .  . 30   .    .         .
 92   .  . 30   .    .         .
 93   1 30 30  90 2700        45
 94   .  . 30   .    .         .
 95   .  .  0   .    .         .
 96   0  0  0   0    0         0
 97   .  . 30   .    .         .
 98   3  5 30 185 5550      92.5
 99   1 30 30  90 2700        45
100   . 20 16   .    .         .
101   2 30 30 150 4500        75
102   0  0  0   0    0         0
103   .  . 30   .    .         .
104   .  . 30   .    .         .
105   .  .  0   .    .         .
106   0  0  0   0    0         0
107   0  0  0   0    0         0
108   0  0  0   0    0         0
109   0  0  0   0    0         0
110   0  0  0   0    0         0
111   .  . 30   .    .         .
112   0  0  0   0    0         0
113   .  .  0   .    .         .
114   2 30 30 150 4500        75
115   .  . 30   .    .         .
116   0  0  0   0    0         0
117   0  0  0   0    0         0
118   .  .  0   .    .         .
119   .  .  0   .    .         .
120   .  .  .   .    .         .
121   .  .  0   .    .         .
122   .  . 15   .    .         .
123   .  .  0   .    .         .
124   .  .  0   .    .         .
125   .  .  0   .    .         .
126   1 30 30  90 2700        45
127   0  0  0   0    0         0
128   0  0  .   0    .         .
129   0  0  0   0    0         0
130   1  0 26  60 1560        26
131   0  0  1   0    0         0
132   .  . 30   .    .         .
133   0  0  0   0    0         0
134   .  .  0   .    .         .
135   .  . 30   .    .         .
136   .  .  0   .    .         .
137   .  .  0   .    .         .
138   0  0  0   0    0         0
139   .  . 30   .    .         .
140   1  0  8  60  480         8
141   0  0  0   0    0         0
142   .  .  0   .    .         .
143   .  .  0   .    .         .
144   0  0  0   0    0         0
145   .  .  0   .    .         .
146   .  .  4   .    .         .
147   .  .  0   .    .         .
148   0  0  0   0    0         0
149   .  . 30   .    .         .
150   .  .  0   .    .         .
151   .  . 30   .    .         .
152   0  0  0   0    0         0
153   .  . 30   .    .         .
154   .  . 30   .    .         .
155   .  .  0   .    .         .
156   .  .  0   .    .         .
157   .  .  0   .    .         .
158   2  0 30 120 3600        60
159   .  .  0   .    .         .
160   .  .  0   .    .         .
161   0  0  0   0    0         0
162   0  0  0   0    0         0
163   .  .  7   .    .         .
164   0  0  0   0    0         0
165   0 30 12  30  360         6
166   0 30  4  30  120         2
167   0  0 30   0    0         0
168   0 15 30  15  450       7.5
169   0 30 30  30  900        15
170   2 15  8 135 1080        18
171   3  0 30 180 5400        90
172   0  0  0   0    0         0
173   1  0  4  60  240         4
174   1  0  4  60  240         4
175   .  .  .   .    .         .
176   0  0  0   0    0         0
177   0  0  0   0    0         0
178   5  0  4 300 1200        20
179   .  .  .   .    .         .
180   3  0  4 180  720        12
181   .  . 30   .    .         .
182   0  0  0   0    0         0
183   .  .  2   .    .         .
184   0  0  0   0    0         0
185   1  0 10  60  600        10
186   .  . 30   .    .         .
187   .  .  0   .    .         .
188   .  .  0   .    .         .
189   0  0  0   0    0         0
190   0 10 10  10  100 1.6666666
191   . 30  4   .    .         .
192   .  .  4   .    .         .
193   2  0  4 120  480         8
194   .  .  0   .    .         .
195   0  0 30   0    0         0
196   0 10 16  10  160  2.666667
197   0  0  0   0    0         0
198   .  .  .   .    .         .
199   0  0 30   0    0         0
200   0  0  0   0    0         0
201   0  0  0   0    0         0
end