To cite sources in German, use the preposition laut (according to).
| According to the new study, the population is decreasing. | Laut der neuen Studie sinkt die Bevölkerung. |
Using "laut" with the Dative Case
The preposition laut can take either the dative or genitive case, but the dative case is much more common in everyday German.
Notice the sentence structure: when a laut phrase starts the sentence, it occupies the first position. To satisfy German's verb-second (V2) rule, the conjugated verb must come immediately after it.
For feminine nouns like die Statistik, the dative article is der:
| According to the statistic, the population in the city is growing. | Laut der Statistik wächst die Bevölkerung in der Stadt. |
For masculine nouns like der Experte, the dative article is dem:
| According to the expert, the income will continue to rise. | Laut dem Experten wird das Einkommen weiter steigen. |
Discussing Data
You will frequently pair laut with official sources of information, such as a census (die Volkszählung).
| According to the census, the income has risen. | Laut der Volkszählung ist das Einkommen gestiegen. |
| According to this source, the proportion of children is decreasing. | Laut dieser Quelle sinkt der Anteil der Kinder. |
When reporting on trends found in these sources, you can summarize what is happening im Durchschnitt (on average).
| On average, the population is now older than before. | Im Durchschnitt ist die Bevölkerung jetzt älter als früher. |
Providing Context with "als"
To explain when a source was analyzed in the past, use the conjunction als (when). Because als is a subordinating conjunction, it sends the conjugated verb to the very end of its clause.
| When he read the study, he found the mistake. | Als er die Studie las, fand er den Fehler. |